There are two main parts to this project. One is the ocean that is comprised of waves moving along the surface and the other is the physics object that inhabits this ocean, in this case a small beach ball. The goal of the simulation is to recreate physics like behaviour in a dynamic ocean we have some parts down and here I will describe what I did to solve the problems I have encountered on the way.
So what is a wave, Webster’s dictionary says: “to motion with the hands or with something held in them in signal or salute”. Well that is not quite what I am looking for, what we want is an oscillating movement, the same thing we have in things like soundwaves and pendulums. So, what happens if we create a basic sine curve, we get something like the gif on the right.
But normally waves don’t look as uniform as this, they have more of a crest and steepness to them. So, we somehow have to make them act more naturally. This is where the Gerstner-wave comes in, this is what is represented on the graph. When adding two sine waves you can create more complex characteristics of the waves. In my example I have only implemented a basic form of Gerster-waves to give it some steepness in the future I am looking to add more directions to give it a more realistic feeling with different sizes of waves and patterns, at this point we have this uniform wave pattern. Now that we know what sort of pattern we want our wave to create, how do we go about and create this in code? First of all we should start of with generating of a plane so that we have some vertices to manipulate in to our decried pattern. Remember we want this to be able to execute in runtime for us to be able to use this data for physics calculations. It just so happens to be that we have a gpu that is quite good at handling vast amount of float values. Here is how I did it
[numthreads(1,1,1)] void GenerateMesh(uint3 id : SV_DispatchThreadID) { float offset = float(SeaResolution * SeaSize * 0.5f); float maxSize = SeaSize * SeaResolution; //Creating verticies & Uvs for (uint i = 0; i < VerticesPerSide; i++) { for (uint j = 0; j < VerticesPerSide; j++) { Vertices[i * VerticesPerSide + j] = float3(j * SeaResolution, 0, i * SeaResolution) - offset; Uvs[i * VerticesPerSide + j] = (float2(j * SeaResolution, i * SeaResolution) - offset); } } int nrVerticies = VerticesPerSide * VerticesPerSide; uint2 index = uint2(0,0); uint triangleIndex = 0; int size = nrVerticies * 6; //Creating triangles for (int k = 0; k < nrVerticies; k++) { index.x = k / VerticesPerSide; index.y = k % VerticesPerSide; if (index.x == SeaSize || index.y == SeaSize) continue; Triangles[triangleIndex++] = index.x + index.y * VerticesPerSide; // (0, 0) bottom left Triangles[triangleIndex++] = index.x + (index.y + 1) * VerticesPerSide; // (0, 1) top left Triangles[triangleIndex++] = index.x + 1 + (index.y + 1) * VerticesPerSide; // (1, 1) top right Triangles[triangleIndex++] = index.x + 1 + (index.y + 1) * VerticesPerSide; // (1, 1) top right Triangles[triangleIndex++] = index.x + 1 + index.y * VerticesPerSide; // (1, 0) bottom right Triangles[triangleIndex++] = index.x + index.y * VerticesPerSide; // (0, 0) bottom left } }
So now we have our plane lets move those vertices! But moving them on the cpu will be very slow and we can’t just do it in a regular shader because we want to access the vertices height and position for our calculations. Well there just happens to be a solution, compute shaders. A compute shader in and of itself does not handle meshes but if we feed it the mesh data it can do the calculations and give it back to the cpu. The cpu tells the gpu what the current time of the simulation is for it to temporally change and what the vertices it is working on. Then it is only a matter of crunching the numbers.
So now we have our plane lets move those vertices! But moving them on the cpu will be very slow and we can’t just do it in a regular shader because we want to access the vertices height and position for our calculations. Well there just happens to be a solution, compute shaders. A compute shader in and of itself does not handle meshes but if we feed it the mesh data it can do the calculations and give it back to the cpu. The cpu tells the gpu what the current time of the simulation is for it to temporally change and what the vertices it is working on. Then it is only a matter of crunching the numbers.
RWStructuredBufferActiveVertices; float WaveLength = 0.5; float Amplitude; float Speed; float2 Direction; uint SizePerSide; float Resolution; float Frequency; float Time; float Steepness; float Gerst; [numthreads(1, 1, 1)] void UpdateMesh(uint3 id : SV_DispatchThreadID) { float3 currentVector = ActiveVertices[id.x + id.y * SizePerSide]; float2 undisturbedVector = float2(id.x, id.y); // float b = 1 - (Steepness * dot(normalize(Direction) float k = 6.28318530718f / WaveLength; float w = dot(normalize(Direction) * k, undisturbedVector) - (6.28318530718f / Frequency) * Time; currentVector.x = undisturbedVector.x - (normalize(Direction) * Amplitude * sin(w)); currentVector.y = Amplitude * cos(w); // currentVector.x -= Resolution * SizePerSide * 0.5f; ActiveVertices[id.x + id.y * SizePerSide] = currentVector; }
Now that we have some ocean looking pattern moving along our plane it is time for us to put those values that we received from the gpu to use. The formula for calculating the buoyance is quite trivial if we have a sphere, that is why we will be simulating a beach ball. All we need is the radius and density of the ball and how submerged it is to create buoyancy force. This is where the height values form the vertices come in. We can calculate where on the ocean the ball is and get the current height of the ocean at the point. Here is how I simulated buoyancy in my project.
public class Buoyancy : MonoBehaviour { [SerializeField]private float _radius = 1; [SerializeField]private float _density = 1; private float _depth; private static readonly float RHO_GRAVITY = Physics.gravity.magnitude * 1000f; //rho = density of water = 1000 Kg/m3 , gravity = 10 m/s2 private Rigidbody _rigidbody; private const float _densityOfAir = 1.2754f; private const float _densityOfWater = 997f; private const float _sphereDragCoefficient = 0.47f; private Plane _plane; void Start() { _rigidbody = gameObject.AddComponent(); _rigidbody.mass = GetVolume(_radius) * _density; _plane = new Plane(); } void FixedUpdate() { float buoyancyForce = RHO_GRAVITY * GetSubmersedVolume(_radius); CalculateDrag(); //Debug.Log(buoyancyForce); _rigidbody.AddForce(Vector3.up * buoyancyForce, ForceMode.Force); } private float GetSubmersedVolume(float radius) { float p = Vector3.Dot(SeaController.GetSurfaceNormal(transform.position),transform.position - SeaController.GetVertexPosition(transform.position)); _depth = radius - p; _depth = Mathf.Clamp(_depth, 0f, radius * 2); return Mathf.PI * ((radius * (_depth * _depth)) - (_depth * _depth * _depth) / 3f) ; } private void CalculateDrag() { //Do air drag if ((transform.position.y - _radius )- SeaController.GetHeight(transform.position) > 0) { float dragForce = (_densityOfAir / 2) * _rigidbody.velocity.magnitude * _rigidbody.velocity.magnitude * _sphereDragCoefficient * _radius * _radius * Mathf.PI; _rigidbody.AddForce(dragForce * (-_rigidbody.velocity.normalized)); } //Do Water drag else { float dragForce = (_densityOfWater / 2) * _rigidbody.velocity.magnitude * _rigidbody.velocity.magnitude * _sphereDragCoefficient * _radius * _radius * Mathf.PI; _rigidbody.AddForce(dragForce * (-_rigidbody.velocity.normalized)); } } private float GetVolume(float radius) { return (4f/3f) * Mathf.PI * radius * radius * radius; } private float GetVolume(Mesh mesh) { float volume = 0; float lowestY = 0; return volume; } }


--- layout: archive title: Zulip Chat Archive permalink: /stream/116395-maths/topic/.60.E2.8A.A2.20S.20.5C.20.7Bs.7D.20.E2.8A.82.20S.60.html ---
S : finset K, s : K, hs : s ∈ S, ⊢ S \ {s} ⊂ S
I was expecting this in the library but I can't find it.
ssubset
is rarely used so there aren't that many lemmas.
The correct lemma is that S - T is a ssubset if T cap S is nonempty I guess
example {s : finset ℕ} (x : ℕ) (h : x ∈ s) : s \ {x} ⊂ s := finset.ssubset_iff.2 ⟨x, by simp, λ y hy, (mem_insert.1 hy).elim (λ hxy, hxy.symm ▸ h) (by simp {contextual := tt})⟩
Thanks a lot.
(deleted)
Any reason you used (h)
not {h}
? I now understand why you used nat ;-)
lemma erase_ssubset {a : α} {s : finset α} (h : a ∈ s) : s.erase a ⊂ s
is in data/finset
Last updated: Apr 24 2020 at 19:02 UTC


University of Alberta ETLC 3rd Floor – Room E3-002
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Click Create to see how demo creates invoice document from scratch and displays data in the GridWeb Control.In this demo ,the editor box is always show.user can also edit through editor box


Alan Bristow, whose obituary appears in today's Guardian, was clearly quite a character. Here was a man who once threw Douglas Bader into a swimming pool (pity it wasn't a pond, I sighed) and called him a “tin-legged git”. I was particularly struck by one little detail, maddeningly not expanded upon, one of those asides that have you clamouring for more information.
Bristow survived into old age to die at 85, just a decade after licensing for production a patent “water bed” for cows…
What? What what what? It is sometimes said that Hooting Yard is “odd” or “wacky”, but the “real world” is infinitely more strange.


pal_search() initializes a pal object. It is used to set the global parameters of 'pal' search.
pal_search(catalogs = c("cpt-city", "color-hex", "paletteer"), type = c("continuous", "discrete", "diverging", "qualitative", "sequential"), return = 25)
| catalogs | character vector; Collections of color palette.
The color palette collections used in pal package come from: |
|---|---|
| type | character vector; Type of palette. The type: |
| return | numeric; Specify the number of palettes to be returned. |


|
SBF
Super bloody fast messaging transport
|
Declaration of functions and structures to handle topics. More...
#include "sbfCommon.h"
Go to the source code of this file.
Macros | |
| #define | SBF_TOPIC_SIZE_LIMIT 255 |
Typedefs | |
| typedef typedefSBF_BEGIN_DECLS struct sbfTopicImpl * | sbfTopic |
Enumerations | |
| enum | sbfTopicType { SBF_TOPIC_PUB, SBF_TOPIC_SUB } |
Functions | |
| sbfTopic | sbfTopic_create (sbfTopicType type, const char *string) |
| Returns a topic handler for a given type and name. A topic name is composed of three sections split by a slash (e.g. neueda/test/mytopic). More... | |
| void | sbfTopic_destroy (sbfTopic topic) |
| Releases all the resources allocated by the given topic handler. More... | |
| sbfTopic | sbfTopic_copy (sbfTopic topic) |
| Create another topic and returns its handler. More... | |
| int | sbfTopic_compare (sbfTopic lhs, sbfTopic rhs) |
| compares two topics and returns => 0 if they are equal, => -1 if lhs is less than rhs, => 1 if rhs is less than lhs. More... | |
| sbfTopicType | sbfTopic_getType (sbfTopic topic) |
| returns the type of topic. More... | |
| const char * | sbfTopic_getTopic (sbfTopic topic) |
| returns the name of the topic. More... | |
| const char * | sbfTopic_getFirst (sbfTopic topic) |
| Returns the first topic name. More... | |
| const char * | sbfTopic_getSecond (sbfTopic topic) |
| Returns the second topic name. More... | |
| const char * | sbfTopic_getThird (sbfTopic topic) |
| Returns the third topic name. More... | |
Declaration of functions and structures to handle topics.
Definition in file sbfTopic.h.
| #define SBF_TOPIC_SIZE_LIMIT 255 |
Maximum size of topic name
Definition at line 17 of file sbfTopic.h.
| typedef typedefSBF_BEGIN_DECLS struct sbfTopicImpl* sbfTopic |
Public declaration for topic type
Definition at line 14 of file sbfTopic.h.
| enum sbfTopicType |
compares two topics and returns => 0 if they are equal, => -1 if lhs is less than rhs, => 1 if rhs is less than lhs.
| lhs | left topic handler. |
| rhs | right topic handler. |
Create another topic and returns its handler.
| topic | the topic handler to be copied. |
| topic | create another topic and returns its handler. |
| sbfTopic sbfTopic_create | ( | sbfTopicType | type, |
| const char * | string | ||
| ) |
Returns a topic handler for a given type and name. A topic name is composed of three sections split by a slash (e.g. neueda/test/mytopic).
| type | the type of topic (SBF_TOPIC_PUB or SBF_TOPIC_SUB). |
| string | the name for the topic to be created. |
| void sbfTopic_destroy | ( | sbfTopic | topic | ) |
Releases all the resources allocated by the given topic handler.
| topic | topic handler. |
| const char* sbfTopic_getFirst | ( | sbfTopic | topic | ) |
Returns the first topic name.
| topic | the topic handler. |
| const char* sbfTopic_getSecond | ( | sbfTopic | topic | ) |
Returns the second topic name.
| topic | the topic handler. |
| const char* sbfTopic_getThird | ( | sbfTopic | topic | ) |
Returns the third topic name.
| topic | the topic handler. |
| const char* sbfTopic_getTopic | ( | sbfTopic | topic | ) |
returns the name of the topic.
| topic | the topic handler. |
| sbfTopicType sbfTopic_getType | ( | sbfTopic | topic | ) |
returns the type of topic.
| topic | the topic handler. |


Egg Sitting
About
Welcome to the Cypress Hills Air Quality Project Website! CHAQ is a collaboration among Cypress Hills Local Development Corporation, Public Laboratory, and MIT's Civic Data Design Lab. Working with Public School 89 in Cypress Hills, the goal of the project is to make and work with low-cost, portable air quality measurement kits and air particulate kits to monitor various air pollutants in Cypress Hills and East New York. While working with the monitors for data collection, students will explore ways of understanding their neighborhood and visualizing the data collected by the monitors.
In Spring 2013, students worked with the Air Quality Eggs as part of their science curriculum. The students focused on collecting indoor air quality data, so as to begin to understand how different housing conditions might impact our lives.
During the Summer 2013, two groups of students are involved in a summer program at PS89. These groups are now using the same eggs to collect outdoor air quality data in the neighborhood, so as to understand what environmental factors might affect the quality of our air.
Read some of the students' and group members' research notes on Public Laboratory's website here.
Check on the local Department of Environmental Conservation Official Air Quality readings here. and the Environmental Protection Agency New York State standards here
All Eggs


Tasmanian Holiday 2015
Waited for ages for my beloved wife’s bag then got that sinking feeling when the carousel stops turning.  Went to the service counter and filled in all the forms for missing luggage. We flew the budget airline Jetstar, if the bag was not found within 24 hours, we’d get a total of $40 to cover expenses - wow. About to take off in the rental car when they called me and said they found the bag. Someone (presumably the owner of the purple bag), had mistakenly taken our black bag which was a totally different size and make. Anyway, things were looking better.
I had booked at hotel in Bronte Park which was a few hours drive. There was enough time to get there before dark. The GPS didn’t quite match my paper map (wouldn’t go without a backup), but we gave it the benefit of the doubt until we ended but in the same spot about an hour later.
At about 7pm, the sealed road turned into gravel just as it started raining. Slowed down to about 50 km/h (30 miles per hour) as I didn’t want to hit anything but as I rounded a corner a wombat ran out, I swerved to avoid it but clipped it with my front left hand side. Backed up to the wombat which was trying to crawl off the road with only its front feet working. I had no choice but to put it out of its misery. Damage was a cracked front bumper bar and two plastic protective pieces under the car. Lucky there was nothing except cosmetic damage to the car, it would have been a bad place to break down with no cell phone coverage and cars going by every 15 minutes or so.
We stayed they night at Bronte Park Village, which is primarily a fishing destination. I can’t think of any other reason why someone would go there. There are four main lakes in the vicinity, Bronte Lagoon, Bradys Lake, Lake Binney and Tungatinah Lagoon. It was a typical one shop village, with the central attraction being the general store and service station.
The next day was a fine day and we passed through some nice scenery between Bronte Park and Cradle Mountain.
We had lunch in the major town of Deloraine. The photo below shows the busiest part of the main street that day.
Deloraine is by the Meander River, a name which I find rather interesting.
We also stopped to pick up some strawberries at Sheffield Berry Gardens.
The drive ended up taking most of the day and we didn’t arrive until the late afternoon at the Cradle Mountain Wilderness Village. We would be roughing it for a couple of days.
Cradle Mountain-Lake St Clair national park is part of the Tasmanian Wildnerness World Heritage Area which covers 20% of Tasmania and is 15,800 square kilometers in area.Cradle Mountain gets its distinctive shape from its Jurassic dolerite columns and is 1545m above sea level. The area below, including Dove Lake, was carved by glacial processes.
It is truly unspoilt and although Cradle Mountain is a premier tourist destination, it is well managed with shuttle services reducing traffic in the park, toilets, strict limits on how many vehicles can be inside the park at any time, and well maintained walking tracks. We walked the Dove Lake Circuit, about a 6 km walk around the lake.
We went back in the evening to take some photos at dusk.
We also met a couple of girls who were about to talk the Overland Track. This is a 6 day 65 km walk (although someone ran it in 7 hours 25 minutes) from Cradle Mountain to Lake St Clair. There are huts along the way. You can normally tell the experience of a hiker by the condition of their packs. In the case of the girls, they were brand new so I hope they know what they are doing.
Our final days were in Hobart. We stayed at the Wrest Point Casino which doesn’t have a 13th floor.
Lots of mussels and oysters growing just outside the hotel.
They have lots of good food in Hobart, particularly seafood and steak.
Spent the rest of the time sightseeing, most interesting was the Tasmanian Museum and Art Gallery. Lots to see there including this 500 year old Huon Pine slice
and this Tasmanian native bark canoe.
Overall our 5 days in Tasmania, particularly Cradle Mountain was too short. We certainly intend to return.


3. Which of the following is the correct subdivision of a movement?
A: movement - section - phrase - period
B: movement - period - phrase - section
C: movement - section - period - phrase
D: movement - phrase - period - section
4. Which of the following is NOT a characteristic of classical music?


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This document covers various components of pinax.apps.basic_profiles.
The named urls in this app should enable the use of of the {% url %} template tag as well as reverse lookups in your project code without having to know the implementation details of this app.
Provides a call back url that uses the pinax.apps.autocomplete_app views to provide data back to the jQuery autocomplete plugin.
Upon GET request, this url will render a template named basic_profiles/profiles.html by default with a list of users in context ordered by either date_joined descending or by username ascending. This is further optionally limited with case-insensitive search against the username field if the query parameter search_terms is provided. Likewise, the ordering defaults to date_joined descending which can be overridden by supplying the query parameter order with the value of name.
Examples:
Show "beth" Users
This would result in the users context variable limited to users such as Beth, Bethany, Marybeth and would be ordered alphabetically by their username.
The value of order and search_terms are also passed to the template as context variables.
This url will render a template named basic_profiles/profile.html by default with is_me and other_user as context variables where is_me is a boolean that indicates whether or not other_user is the same as the authenticated user making the request.
| keyword arguments: | |
|---|---|
| The username for the profile to view that matches (?P<username>[\w\._-]+) |
This url, when POSTed to will process the variables through a pinax.apps.basic_profiles.forms.ProfileForm instance, otherwise it will process a GET request by rendering basic_profiles/profile_edit.html by default for regular requests and basic_profiles/profile_edit_facebox.html for ajax calls. It renders both of these templates with an instance of the pinax.apps.basic_profiles.ProfileForm as profile_form and an instance of pinax.apps.basic_profiles.models.Profile as profile.
Templates should be placed in an basic_profiles/ folder at the root of one of your template search paths.
| context: | users, order, search_terms |
|---|
| context: | is_me, other_user |
|---|
| context: | profile, profile_form |
|---|
| context: | profile, profile_form |
|---|
Profile(id, user_id, name, about, location, website)


DB4SCI is an easy-to-use, web-based, self-service database deployment application. Users can select a database type and version and DB4SCI creates a stand-alone database instance for the user. Each deployed database instance is a separate container with its own private data volumes. Multiple versions of PostgreSQL, MariaDB, Mongo and Neo4j can be selected. DB4SCI is a fully containerized Flask application.
DB4SCI was designed provide to nimble, friction-less service to facilitate Fred Hutchinson Cancer Research Center’s research and administration. We wanted to make it easy to create a database and to promote database usage for scientific computing.
Users do not have to worry about protecting their data. DB4SCI performs native database backups for containers. Backups are kept on-site and replicated to Amazon S3 storage.
DB4SCI offers popular database deployment options like MariaDB with encryption at rest and TLS with server/client certs. Configure PostgreSQL with multicore parallelization enabled. Neo4j is deployed in secure mode with https enabled. MongoDB is configured with authentication.
DB4SCI offers high performance if it is deployed on high-end hardware. Why build something that is slow? Our local deployment uses ultra-low latency Intel Optane NVMe storage. DB4SCI can be deployed on Docker Swarm to provide a highly reliable and scalable database service. DB4SCI can also be deployed in any cloud that provides virtual machines with fast storage.
DB4SCI supports multiple storage volumes. Databases can be configured on different storage platforms to support production or development. On the create screen administrators can enable users to choose different storage types. Access to storage types can be managed by database type and user ID. Multi volume support has allowed us to offer encryption at rest for PostgreSQL by providing an encrypted filesystem as a storage option.


No routes found that satisfy the route specification. Try setting an arrival deadline further into the future.
Route option
##{itineraryStatus.index + 1}
No routes found that satisfy the route specification. Try setting an arrival deadline further into the future.


Sample LC3 Webhook Application
How to use?
1. Click "Create webhook" button below
2. Start chat and type "What time is it?"
3. The message with current time will appear in chat.
4. Don't worry this message will be only visible for you ;)
Create webhook
Delete all webhooks


EXAMINATIONS
|
HAMS ARE NOT CITIZEN BAND RADIO OPERATORS The Federal Communications Commission (FCC) requires every Amateur Radio operator to pass at least one of its three tests to receive a license. The more licenses you pass, the more privileges you receive on the radio. Becoming a ham is not difficult, however it does require you to do some work to pass the examinations. If you are not willing to put in some time studying for the required examination(s), you may want to take up a different hobby. |
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LICENSES There are currently three license classes: Technician, General and Amateur Extra. The higher grade the license you hold, the more privileges you will enjoy. Some hams never progress beyond the entry level Technician license, and they are happy to just have the privileges that license conveys. With this license they are limited to fewer bands, and a majority of Technician license holders can be found working on VHF and UHF frequencies. The General Class license is for those who want to learn more about electronics and gain more High Frequency privileges. This enables them the opportunity to talk farther and to use more bands to communicate. The Amateur Extra license is the highest license class available. A more thorough understanding of electronics is required for this exam, but it also conveys all the privileges available to the hobbyists. |
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PREPARING FOR YOUR EXAMINATION In years past, those who aspired to attain a ham radio license had to learn the Morse code at prescribed speeds for each license class. This requirement was eliminated a few years ago. Now, you need only pass a multiple choice test to become licensed. The current Question Pools for each of the exams are also available on line at http://www.arrl.org/question-pools. If you want to purchase a basic license study guide for any of the three classes of licenses, there are two we would recommend. One is published by ARRL, and the other is authored by Gorden West. These can easily be found by a search of the Internet. Wherever you get it, just be sure to get then newest edition, as the question pools change from time to time. Recently, our club has been recommending the free downloadable No-Nonsense license study guides by KB6NU. Our members have commented they have found them to be very useful and easier to use than the books listed above.
Our club periodically offers free classes to help those who are interested in joining our hobby. We have found, however, that those who study at least an additional hour a day at home have the best chance of passing their exam on the first try. Learning what you can on your own, and then bringing your questions to the classes, is the most effective way of learning. The passing grade on ham radio exams is 74%. We have found that on-line practice tests can be a valuable part of the learning process when studying for exams. As you progress toward your goal and are studying the license manual, supplement your study by taking at least two on-line exams a day. When you are consistently receiving scores of 90% and above, you should be ready for your exam. On-line practice tests are available at: http://www.eham.net/exams/ http://www.qrz.com/xtest2.html |
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QUESTIONS? If you have further questions, feel free to contact our club at the e-mail address on this website's Index page, or call<PHONE_NUMBER>. |


From wherever you come and for any destination you want to leave we will be happy to accompany you and / or pick you up at the airport. The service covers all Italian and foreign airports and can make you reach both snow-covered ski resorts and sunny seaside resorts. Transportation can be arranged for you, for your loved one or for an important guest.
For business trips, to enjoy an evening without the thought of driving, for long trips even more days, to be accompanied in the best shopping places without thinking of parking, rely on our services that guarantee punctuality, reliability, comfort and security. It is possible to book the service even for long periods with continuous collaboration relationships.
Are you a sportsman? Do you need a safe support to take you to the locations where your favorite activities take place? We will take you to the place of departure, we will come to pick you up on arrival and we will keep your equipment in our means so you can enjoy your adventure with absolute carefreeness.
You are on holiday? Do you want to enliven your guests with a tour of the most beautiful places in the surrounding area? We will take care to take you to admire the natural and artistic beauty of the area.
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LoadData


This example integrates the following integrands with function quadratureLobatto and compares the result with an analytical solution. The examples also demonstrate how additional input arguments to the integrand function can be passed as additional arguments. The following integrals are computed:
function quadratureLobatto1 extends Modelica.Icons.Function; import Modelica.Utilities.Streams.print; input Real tolerance = 1e-5 "Error tolerance of integral values"; end quadratureLobatto1;


--- title: "Basic Card with Background Color" description:
Many variations are available matching the color palette. This card for example, is using h-bck__secondary--dark
class helper for its background color. For other variations, replace the word secondary
in the class with any of accent
, accent2
, accent3
, accent4
, primary
, primary2
, secondary
, background
. Remember to use evo_h-txt-light
or evo_h-txt-light2
on the text.
Replenish, earth tree replenish give, he air days you, after i first them dry Seed. Created own every one lights.


What is Rails?
5.30.15
Before DBC, I had often heard about Ruby on Rails, but never thought of them seperatly. Now that we know some basic Ruby programming language, what is this other piece Rails? A good question to ask at this point is, where would the HTML,CSS,Ruby,JavaScript,SQL code that I have learned go? How will it all work together to enable a decent website? What we need to achieve something like that is an environment with predefined "rules of engagment" among different pieces or a Framework. Thats exactly what Rails provides us. Its a framework that setups a methodology on how a decent website will function. This website will include different HTML webpages with CSS or Javascript and have some Ruby plus SQL code to manage our databases on the servers. Rails defines this front-end and back-end design theme as well as enables the communication between the two.


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CCCLOTHES
MEN'S TOPS
LINEN BLAZER
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Men's outfit
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Men's pattern shirts
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top 5 largest cities
These are the top 5 cities in the world as defined by their city proper, urban area, and the metropolitan region.
- China, Shanghai
Population: City 21,516,000 // Urban 21,009,000 // Metro 21,148,000
- China, Beijing
Population: City 21,516,000 // Urban 21,009,000 // Metro 21,148,000
- Brazil, Sâo Paulo
Population: City 21,292,893 // Urban 20,365,000 // Metro 36,842,102
- India, Delhi
Population: City 16,787,941 // Urban 24,998,000 // Metro 21,753,486
- Pakistan, Karachi
Population: City 21,000,000 // Urban 22,123,000
Source: https://en.wikipedia.org/wiki/World%27s_largest_cities


How do I... Wait for another bot to finish an action?
When writing tests, you might try to have one bot wait for another bot to complete an action. This can be useful for "multiple session" testing. Coordinating these two concurrent processes can be challenging, but you have a few options.
Switch users, not bots
Depending on what you are trying to test, the simplest approach is to have a single bot that authenticates as the first user, takes some actions, then authenticates as the second user and continues. This is very clear to understand and orchestrate, but it does mean that the two sessions are happening serially instead of concurrently. Nonetheless, it can be useful, not only for tests, but also to run some simple set up.
A very similar approach is to run the setup in the "pre" tree of an integration test. Just keep in mind that the pre tree is a separate bot, so the context will be lost when the pre tree completes.
Use a wait
If you want to have separate bots, you have to coordinate between them somehow. The most naive way of doing so is to just have the second bot go idle for however many seconds you think the first bot needs to finish its action.
This is not a great solution though. At best, you are introducing extra unnecessary time into your tests if you guess too long of a pause. At worst, the first bot might take longer than expected for some reason, and your pause will be too short, leading to flaky tests.
Set a flag in SharedData
A more reliable approach is to have the second bot go into a retry loop, checking
for a flag set in SharedData
. When the first bot finishes its action, it just
needs to set that flag.
Rely on the system under test
Perhaps the best approach, when possible, is to check the state of the system under test to tell if the first bot has finished its work. You would use a similar retry loop with a query against the system, or if you have a second channel for syncing, you would check against the context for the required condition.


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An attractive and vibrant holiday destination for visitors to the Great Barrier Reef. Great beaches, landscaped waterfront and, of course, the diving.
Position 19°15′23″S, 146°49′6″E.
For full details of Clearance see Australia/Formalities.
On arrival clearly display the 'Q' flag and call The Breakwater Marina on VHF channel 10. Berth at the fuel dock located immediately inside the marina entrance on the Starboard side. It is imperative that vessels clearing customs DO NOT secure to the fuel dock until Customs officers are onsite. Vessels arriving after hours will be required to stand-off in the breakwater area outside the marina entrance.
Last updated January 2014.
The Breakwater Marina is situated close to the city centre with supermarkets and all amenities.
There is also a marina at Magnetic Island, just 5nm north of the town.
The Duck Pond offers a free anchorage sheltered against the prevailing winds.
It may also be possible to obtain a berth in the old marina in the Ross River. This is approached via the commercial port and past the ferry terminal.
Last updated January 2014.


fkReconstruction reference pages
uireconstruction
synopsis
gui for stimulus reconstruction exploration
syntax
UIRECONSTRUCTION(r)
description
UIRECONSTRUCTION(r) where r is a reconstruction engine
Toolbox page
reconstructengine


I took 600mg Adrafinil at 8 a.m. on an empty stomach along with my usual morning gingko, tea, blood pressure meds, etc.
Like the first time I tried piracetam, I noticed within an hour that women looked better. I did not feel much of a buzz until 4 hours later when I went into work. I applied myself with intensity and focus but I felt too revved to be at ease. I was more talkative, alert, and faster paced but it had what felt like a bit of an amphetamine edge. It was difficult to relax or even smile though my mood was definitely good.
Eight hours into it I definitely felt wired but not terribly anxious though I was worried enough to check my blood pressure. It was way high (145/92). By hour 16 I was compelled to write some poetry, something I haven't done in years.
I went to bed a few hours after my usual time but my sleep was very thin and spotty. Next morning I'm still in a good mood considering not sleeping.
Sex is better, too.
Experience Reports are the writings and opinions of the individual authors who submit them.
Some of the activities described are dangerous and/or illegal and none are recommended by Erowid.


@* * Copyright 2023 HM Revenue & Customs * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *@ @import models.resident._ @import models.resident.properties._ @this( deductionsSummaryPartial: playHelpers.deductionsSummaryPartial, checkYourAnswersPartial: playHelpers.checkYourAnswersPartial, ) @(gainAnswers: YourAnswersSummaryModel, deductionAnswers: ChargeableGainAnswers, result: ChargeableGainResultModel, taxYear: TaxYearModel, totalCosts: BigDecimal)(implicit request: Request[_], messages: Messages, lang: Lang)


This is what we provide to our visiters.
This is a brief history about planes and the developments of flight.
We get up close to planes and show front row seats for our guests through the pilot seats and our performance from trained pilot.
We give our guests the feel of a real flight simulations to experience the skies.


HTML5 Canvas
Learning to draw with the Canvas API.
References:
Resizing images in canvas
Working with Canvas gradients
Creating linear gradients
Radial gradient API
Getting mouse position in canvas
Adding click events in JavaScript
Got a question? feel free to contact me.
To learn more about this course visit my site
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jstat - Java Virtual Machine Statistics Monitoring Tool
f3 f3jstat [ f2generalOption | f2outputOptions f2vmid [f2interval[s|ms] [f2count]] ]
generalOption A single general command-line option (-help or -options)
outputOptions One or more output options, consisting of a single f2statOption, plus any of the -t, -h, and -J options.
vmid Virtual machine identifier, a string indicating the target Java virtual machine (JVM). The general syntax is
f3 [f4protocolf3:][//]f4lvmid[@f2hostname[:f2port]/f2servername]
The syntax of the vmid string largely corresponds to the syntax of a URI. The f2vmid can vary from a simple integer representing a local JVM to a more complex construction specifying a communications protocol, port number, and other implementation-specific values. See Virtual Machine Identifier for details.
interval[s|ms] Sampling interval in the specified units, seconds (s) or milliseconds (ms). Default units are milliseconds. Must be a positive integer. If specified, f3jstat will produce its output at each interval.
count Number of samples to display. Default value is infinity; that is, f3jstat displays statistics until the target JVM terminates or the f3jstat command is terminated. Must be a positive integer.
The f3jstat tool displays performance statistics for an instrumented HotSpot Java virtual machine (JVM). The target JVM is identified by its virtual machine identifier, or f2vmid option described below.
f3NOTE: This utility is unsupported and may not be available in future versions of the JDK. It is not currently available on Windows 98 and Windows ME. platforms.
VIRTUAL MACHINE IDENTIFIER
The syntax of the f2vmid string largely corresponds to the syntax of a URI:
f3 [f4protocolf3:][//]f4lvmid[@f2hostname][:f2port][/f2servername]
protocol The communications protocol. If the f2protocol is omitted and a f2hostname is not specified, the default protocol is a platform specific optimized local protocol. If the f2protocol is omitted and a f2hostname is specified, then the default protocol is f3rmi.
lvmid The local virtual machine identifier for the target JVM. The f2lvmid is a platform-specific value that uniquely identifies a JVM on a system. The f2lvmid is the only required component of a virtual machine identifier. The f2lvmid is typically, but not necessarily, the operating system's process identifier for the target JVM process. You can use the jps(1) command to determine the f2lvmid. Also, you can determine f2lvmid on Unix platforms with the f3ps command, and on Windows with the Windows Task Manager.
hostname A hostname or IP address indicating the target host. If f2hostname is omitted, then the target host is the local host.
port The default port for communicating with the remote server. If the f2hostname is omitted or the f2protocol specifies an optimized, local protocol, then f2port is ignored. Otherwise, treatment of the f2port parameter is implementation specific. For the default f3rmi protocol, the f2port indicates the port number for the rmiregistry on the remote host. If f2port is omitted, and f2protocol indicates f3rmi, then the default rmiregistry port (1099) is used.
servername The treatment of this parameter depends on implementation. For the optimized local protocol, this field is ignored. For the f3rmi protocol, it represents the name of the RMI remote object on the remote host.
The f3jstat command supports two types of options, general options and output options. General options cause f3jstat to display simple usage and version information. Output options determine the content and format of the statistical output.
f3NOTE: All options, and their functionality are subject to change or removal in future releases.
GENERAL OPTIONS
If you specify one of the general options, you cannot specify any other option or parameter.
-help Display help message.
-options Display list of statistics options. See the Output Options section below.
OUTPUT OPTIONS
If you do not specify a general option, then you can specify output options. Output options determine the content and format of f3jstat's output, and consist of a single f2statOption, plus any of the other output options (-h, -t, and -J). The f2statOption must come first.
Output is formatted as a table, with columns are separated by spaces. A header row with titles describes the columns. Use the f3-h option to set the frequency at which the header is displayed. Column header names are generally consistent between the different options. In general, if two options provide a column with the same name, then the data source for the two columns are the same.
Use the f3-t option to display a time stamp column, labeled f2Timestamp as the first column of output. The f2Timestamp column contains the elapsed time, in seconds, since startup of the target JVM. The resolution of the time stamp is dependent on various factors and is subject to variation due to delayed thread scheduling on heavily loaded systems.
Use the f2interval and f2count parameters to determine how frequently and how many times, respectively, f3jstat displays its output.
f3NOTE: You are advised not to write scripts to parse f3jstat's output since the format may change in future releases. If you choose to write scripts that parse f3jstat output, expect to modify them for future releases of this tool.
-statOption Determines the statistics information that f3jstat displays. The following table lists the available options. Use the f3-options general option to display the list of options for a particular platform installation.
Statistics on the behavior of the class loader.
Statistics of the behavior of the HotSpot Just-in-Time compiler.
Statistics of the behavior of the garbage collected heap.
Statistics of the capacities of the generations and their corresponding spaces.
Summary of garbage collection statistics (same as f3-gcutil), with the cause of the last and current (if applicable) garbage collection events.
Statistics of the behavior of the new generation.
Statistics of the sizes of the new generations and its corresponding spaces.
Statistics of the behavior of the old and permanent generations.
Statistics of the sizes of the old generation.
Statistics of the sizes of the permanent generation.

HotSpot compilation method statistics.h'|n(40u'f3Optionh'|n(41u'f3Displays... h'|n(40u'classh'|n(41u' h'|n(40u'compilerh'|n(41u' h'|n(40u'gch'|n(41u' h'|n(40u'gccapacityh'|n(41u' h'|n(40u'gccauseh'|n(41u' h'|n(40u'gcnewh'|n(41u' h'|n(40u'gcnewcapacityh'|n(41u' h'|n(40u'gcoldh'|n(41u' h'|n(40u'gcoldcapacityh'|n(41u' h'|n(40u'gcpermcapacityh'|n(41u' h'|n(40u'gcutilh'|n(41u' h'|n(40u'printcompilationh'|n(41u' -h n Display a column header every f2n samples (output rows), where f2n is a positive integer. Default value is 0, which displays the column header above the first row of data. -t Display a timestamp column as the first column of output. The timestamp is the time since the start time of the target JVM. -JjavaOption Pass f2javaOption to the f3java application launcher. For example, f3-J-Xms48m sets the startup memory to 48 megabytes. For a complete list of options, see java(1)STATOPTIONS AND OUTPUT
The following tables summarize the columns that f3jstat outputs for each f2statOption.
-class Option
Number of classes unloaded.
Number of Kbytes unloaded.
Time spent performing class load and unload operations.h'|n(40u'Class Loader Statisticsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'Loadedh'|n(41u'Number of classes loaded. h'|n(40u'Bytesh'|n(41u'Number of Kbytes loaded. h'|n(40u'Unloadedh'|n(41u' h'|n(40u'Bytesh'|n(41u' h'|n(40u'Timeh'|n(41u'-compiler Option
Number of compilation tasks performed.
Number of compilation tasks that failed.
Number of compilation tasks that were invalidated.
Time spent performing compilation tasks.
Compile type of the last failed compilation.
Class name and method for the last failed compilation.h'|n(40u'HotSpot Just-In-Time Compiler Statisticsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'Compiledh'|n(41u' h'|n(40u'Failedh'|n(41u' h'|n(40u'Invalidh'|n(41u' h'|n(40u'Timeh'|n(41u' h'|n(40u'FailedTypeh'|n(41u' h'|n(40u'FailedMethodh'|n(41u'-gc Option
Current survivor space 0 capacity (KB).
Current survivor space 1 capacity (KB).
Survivor space 0 utilization (KB).
Survivor space 1 utilization (KB).
Current eden space capacity (KB).
Eden space utilization (KB).
Current old space capacity (KB).
Old space utilization (KB).
Current permanent space capacity (KB).
Permanent space utilization (KB).
Number of young generation GC Events.

Maximum new generation capacity (KB).
Current new generation capacity (KB).
Current survivor space 0 capacity (KB).
Current survivor space 1 capacity (KB).
Current eden space capacity (KB).
Minimum old generation capacity (KB).
Maximum old generation capacity (KB).
Current old generation capacity (KB).
Current old space capacity (KB).
Minimum permanent generation capacity (KB).
Maximum Permanent generation capacity (KB).
Current Permanent generation capacity (KB).
Current Permanent space capacity (KB).
Number of Young generation GC Events.h'|n(40u'Memory Pool Generation and Space Capacitiesh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'NGCMNh'|n(41u' h'|n(40u'NGCMXh'|n(41u' h'|n(40u'NGCh'|n(41u' h'|n(40u'S0Ch'|n(41u' h'|n(40u'S1Ch'|n(41u' h'|n(40u'ECh'|n(41u' h'|n(40u'OGCMNh'|n(41u' h'|n(40u'OGCMXh'|n(41u' h'|n(40u'OGCh'|n(41u' h'|n(40u'OCh'|n(41u' h'|n(40u'PGCMNh'|n(41u' h'|n(40u'PGCMXh'|n(41u' h'|n(40u'PGCh'|n(41u' h'|n(40u'PCh'|n(41u' h'|n(40u'YGCh'|n(41u' h'|n(40u'FGCh'|n(41u'Number of Full GC Events.-gccause Option
This option displays the same summary of garbage collection statistics as the f3-gcutil option, but includes the causes of the last garbage collection event and (if applicable) the current garbage collection event. In addition to the columns listed for f3-gcutil, this option adds the following columns:
Cause of last Garbage Collection.
Cause of current Garbage Collection.h'|n(40u'Garbage Collection Statistics, Including GC Eventsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'LGCCh'|n(41u' h'|n(40u'GCCh'|n(41u'-gcnew Option
Current survivor space 0 capacity (KB).
Current survivor space 1 capacity (KB).
Survivor space 0 utilization (KB).
Survivor space 1 utilization (KB).
Maximum tenuring threshold.
Desired survivor size (KB).
Current eden space capacity (KB).
Eden space utilization (KB).
Number of young generation GC events.

Maximum new generation capacity (KB).
Current new generation capacity (KB).
Maximum survivor space 0 capacity (KB).
Current survivor space 0 capacity (KB).
Maximum survivor space 1 capacity (KB).
Current survivor space 1 capacity (KB).
Maximum eden space capacity (KB).
Current eden space capacity (KB).
Number of young generation GC events.h'|n(40u'New Generation Space Size Statisticsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'NGCMNh'|n(41u' h'|n(40u'NGCMXh'|n(41u' h'|n(40u'NGCh'|n(41u' h'|n(40u'S0CMXh'|n(41u' h'|n(40u'S0Ch'|n(41u' h'|n(40u'S1CMXh'|n(41u' h'|n(40u'S1Ch'|n(41u' h'|n(40u'ECMXh'|n(41u' h'|n(40u'ECh'|n(41u' h'|n(40u'YGCh'|n(41u' h'|n(40u'FGCh'|n(41u'Number of Full GC Events.-gcold Option
Current permanent space capacity (KB).
Permanent space utilization (KB).
Current old space capacity (KB).
old space utilization (KB).
Number of young generation GC events.

Maximum old generation capacity (KB).
Current old generation capacity (KB).
Current old space capacity (KB).
Number of young generation GC events.

Maximum permanent generation capacity (KB).
Current permanent generation capacity (KB).
Current permanent space capacity (KB).
Number of young generation GC events.

Total garbage collection time.h'|n(40u'Permanent Generation Statisticsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'PGCMNh'|n(41u' h'|n(40u'PGCMXh'|n(41u' h'|n(40u'PGCh'|n(41u' h'|n(40u'PCh'|n(41u' h'|n(40u'YGCh'|n(41u' h'|n(40u'FGCh'|n(41u'Number of full GC events. h'|n(40u'FGCTh'|n(41u' h'|n(40u'GCTh'|n(41u'-gcutil Option
Survivor space 0 utilization as a percentage of the space's current capacity.
Survivor space 1 utilization as a percentage of the space's current capacity.
Eden space utilization as a percentage of the space's current capacity.
Old space utilization as a percentage of the space's current capacity.
Permanent space utilization as a percentage of the space's current capacity.
Number of young generation GC events.

Total garbage collection time.h'|n(40u'Summary of Garbage Collection Statisticsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'S0h'|n(41u' h'|n(40u'S1h'|n(41u' h'|n(40u'Eh'|n(41u' h'|n(40u'Oh'|n(41u' h'|n(40u'Ph'|n(41u' h'|n(40u'YGCh'|n(41u' h'|n(40u'YGCTh'|n(41u' h'|n(40u'FGCh'|n(41u'Number of full GC events. h'|n(40u'FGCTh'|n(41u' h'|n(40u'GCTh'|n(41u'-printcompilation Option
Number of compilation tasks performed by the most recently compiled method.
Number of bytes of bytecode of the most recently compiled method.
Compilation type of the most recently compiled method.
Class name and method name identifying the most recently compiled method. Class name uses "/" instead of "." as namespace separator. Method name is the method within the given class. The format for these two fields is consistent with the HotSpot - f3XX:+PrintComplation option.h'|n(40u'HotSpot Compiler Method Statisticsh'|n(41u' h'|n(40u'f3Columnh'|n(41u'f3Description h'|n(40u'Compiledh'|n(41u' h'|n(40u'Sizeh'|n(41u' h'|n(40u'Typeh'|n(41u' h'|n(40u'Methodh'|n(41u'EXAMPLES
This section presents some examples of monitoring a local JVM with a f2lvmid of 21891.
Using the gcutil option
This example attaches to f2lvmid 21891 and takes 7 samples at 250 millisecond intervals and displays the output as specified by the f3-gcutil option.
f3 f3jstat -gcutil 21891 250 7
S0 S1 E O P YGC YGCT FGC FGCT GCT
12.44 0.00 27.20 9.49 96.70 78 0.176 5 0.495 0.672
12.44 0.00 62.16 9.49 96.70 78 0.176 5 0.495 0.672
12.44 0.00 83.97 9.49 96.70 78 0.176 5 0.495 0.672
0.00 7.74 0.00 9.51 96.70 79 0.177 5 0.495 0.673
0.00 7.74 23.37 9.51 96.70 79 0.177 5 0.495 0.673
0.00 7.74 43.82 9.51 96.70 79 0.177 5 0.495 0.673
0.00 7.74 58.11 9.51 96.71 79 0.177 5 0.495 0.673
The output of this example shows that a young generation collection occurred between the 3rd and 4th sample. The collection took 0.001 seconds and promoted objects from the eden space (E) to the old space (O), resulting in an increase of old space utilization from 9.49% to 9.51%. Before the collection, the survivor space was 12.44% utilized, but after this collection it is only 7.74% utilized.
Repeating the column header string
This example attaches to f2lvmid 21891 and takes samples at 250 millisecond intervals and displays the output as specified by f3-gcutil option. In addition, it uses the f3-h3 option to output the column header after every 3 lines of data.
f3 f3jstat -gcnew -h3 21891 250
S0C S1C S0U S1U TT MTT DSS EC EU YGC YGCT
64.0 64.0 0.0 31.7 31 31 32.0 512.0 178.6 249 0.203
64.0 64.0 0.0 31.7 31 31 32.0 512.0 355.5 249 0.203
64.0 64.0 35.4 0.0 2 31 32.0 512.0 21.9 250 0.204
S0C S1C S0U S1U TT MTT DSS EC EU YGC YGCT
64.0 64.0 35.4 0.0 2 31 32.0 512.0 245.9 250 0.204
64.0 64.0 35.4 0.0 2 31 32.0 512.0 421.1 250 0.204
64.0 64.0 0.0 19.0 31 31 32.0 512.0 84.4 251 0.204
S0C S1C S0U S1U TT MTT DSS EC EU YGC YGCT
64.0 64.0 0.0 19.0 31 31 32.0 512.0 306.7 251 0.204
In addition to showing the repeating header string, this example shows that between the 2nd and 3rd samples, a young GC occurred. Its duration was 0.001 seconds. The collection found enough live data that the survivor space 0 utilization (S0U) would would have exceeded the desired survivor Size (DSS). As a result, objects were promoted to the old generation (not visible in this output), and the tenuring threshold (TT) was lowered from 31 to 2.
Another collection occurs between the 5th and 6th samples. This collection found very few survivors and returned the tenuring threshold to 31.
Including a time stamp for each sample
This example attaches to f2lvmid 21891 and takes 3 samples at 250 millisecond intervals. The f3-t option is used to generate a time stamp for each sample in the first column.
f3 f3jstat -gcoldcapacity -t 21891 250 3
Timestamp OGCMN OGCMX OGC OC YGC FGC FGCT GCT
150.1 1408.0 60544.0 11696.0 11696.0 194 80 2.874 3.799
150.4 1408.0 60544.0 13820.0 13820.0 194 81 2.938 3.863
150.7 1408.0 60544.0 13820.0 13820.0 194 81 2.938 3.863
The f2Timestamp column reports the elapsed time in seconds since the start of the target JVM. In addition, the f3-gcoldcapacity output shows the old generation capacity (OGC) and the old space capacity (OC) increasing as the heap expands to meet allocation and/or promotion demands. The old generation capacity (OGC) has grown to from 11696 KB to 13820 KB after the 81st Full GC (FGC). The maximum capacity of the generation (and space) is 60544 KB (OGCMX), so it still has room to expand.
Monitor instrumentation for a remote JVM
This example attaches to f2lvmid 40496 on the system named f2remote.domain using the f3-gcutil option, with samples taken every second indefinitely.
f3 f3jstat -gcutil<EMAIL_ADDRESS>1000
The f2lvmid is combined with the name of the remote host to construct a f2vmid of<EMAIL_ADDRESS>This f2vmid results in the use of the f3rmi protocol to communicate to the default f3jstatd server on the remote host. The f3jstatd server is located using the f3rmiregistry on f2remote.domain that is bound to the default f3rmiregistry port (port 1099).
SEE ALSO
o java(1) - the Java Application Launcher
o jps(1) - the Java Process Status Application
o jstatd(1) - the jvmstat daemon
o rmiregistry(1) - the Java Remote Object Registry


public class MethodHandles extends Object
| Modifier and Type | Class and Description |
|---|---|
static class |
MethodHandles.Lookup
A lookup object is a factory for creating method handles,
when the creation requires access checking.
|
| Modifier and Type | Method and Description |
|---|---|
static MethodHandle |
arrayElementGetter(Class<?> arrayClass)
Produces a method handle giving read access to elements of an array.
|
static MethodHandle |
arrayElementSetter(Class<?> arrayClass)
Produces a method handle giving write access to elements of an array.
|
static MethodHandle |
catchException(MethodHandle target,
Class<? extends Throwable> exType,
MethodHandle handler)
Makes a method handle which adapts a target method handle,
by running it inside an exception handler.
|
static MethodHandle |
collectArguments(MethodHandle target,
int pos,
MethodHandle filter)
Adapts a target method handle by pre-processing
a sub-sequence of its arguments with a filter (another method handle).
|
static MethodHandle |
constant(Class<?> type,
Object value)
Produces a method handle of the requested return type which returns the given
constant value every time it is invoked.
|
static MethodHandle |
dropArguments(MethodHandle target,
int pos,
Class<?>... valueTypes)
Produces a method handle which will discard some dummy arguments
before calling some other specified target method handle.
|
static MethodHandle |
dropArguments(MethodHandle target,
int pos,
List<Class<?>> valueTypes)
Produces a method handle which will discard some dummy arguments
before calling some other specified target method handle.
|
static MethodHandle |
exactInvoker(MethodType type)
Produces a special invoker method handle which can be used to
invoke any method handle of the given type, as if by
invokeExact . |
static MethodHandle |
explicitCastArguments(MethodHandle target,
MethodType newType)
Produces a method handle which adapts the type of the
given method handle to a new type by pairwise argument and return type conversion.
|
static MethodHandle |
filterArguments(MethodHandle target,
int pos,
MethodHandle... filters)
Adapts a target method handle by pre-processing
one or more of its arguments, each with its own unary filter function,
and then calling the target with each pre-processed argument
replaced by the result of its corresponding filter function.
|
static MethodHandle |
filterReturnValue(MethodHandle target,
MethodHandle filter)
Adapts a target method handle by post-processing
its return value (if any) with a filter (another method handle).
|
static MethodHandle |
foldArguments(MethodHandle target,
MethodHandle combiner)
Adapts a target method handle by pre-processing
some of its arguments, and then calling the target with
the result of the pre-processing, inserted into the original
sequence of arguments.
|
static MethodHandle |
guardWithTest(MethodHandle test,
MethodHandle target,
MethodHandle fallback)
Makes a method handle which adapts a target method handle,
by guarding it with a test, a boolean-valued method handle.
|
static MethodHandle |
identity(Class<?> type)
Produces a method handle which returns its sole argument when invoked.
|
static MethodHandle |
insertArguments(MethodHandle target,
int pos,
Object... values)
Provides a target method handle with one or more bound arguments
in advance of the method handle's invocation.
|
static MethodHandle |
invoker(MethodType type)
Produces a special invoker method handle which can be used to
invoke any method handle compatible with the given type, as if by
invoke . |
static MethodHandles.Lookup |
lookup()
Returns a
lookup object with
full capabilities to emulate all supported bytecode behaviors of the caller. |
static MethodHandle |
permuteArguments(MethodHandle target,
MethodType newType,
int... reorder)
Produces a method handle which adapts the calling sequence of the
given method handle to a new type, by reordering the arguments.
|
static MethodHandles.Lookup |
publicLookup()
Returns a
lookup object which is trusted minimally. |
static <T extends Member> |
reflectAs(Class<T> expected,
MethodHandle target)
Performs an unchecked "crack" of a
direct method handle.
|
static MethodHandle |
spreadInvoker(MethodType type,
int leadingArgCount)
Produces a method handle which will invoke any method handle of the
given
type , with a given number of trailing arguments replaced by
a single trailing Object[] array. |
static MethodHandle |
throwException(Class<?> returnType,
Class<? extends Throwable> exType)
Produces a method handle which will throw exceptions of the given
exType . |
public static MethodHandles.Lookup lookup()
lookup object
with
full capabilities to emulate all supported bytecode behaviors of the caller.
These capabilities include private access to the caller.
Factory methods on the lookup object can create
direct method handles
for any member that the caller has access to via bytecodes,
including protected and private fields and methods.
This lookup object is a capability which may be delegated to trusted agents.
Do not store it in place where untrusted code can access it.
This method is caller sensitive, which means that it may return different values to different callers.
For any given caller class C
, the lookup object returned by this call
has equivalent capabilities to any lookup object
supplied by the JVM to the bootstrap method of an
invokedynamic instruction
executing in the same caller class C
.
public static MethodHandles.Lookup publicLookup()
lookup object
which is trusted minimally.
It can only be used to create method handles to
publicly accessible fields and methods.
As a matter of pure convention, the lookup class
of this lookup object will be Object
.
Discussion:
The lookup class can be changed to any other class C
using an expression of the form
publicLookup().in(C.class)
.
Since all classes have equal access to public names,
such a change would confer no new access rights.
A public lookup object is always subject to
security manager checks.
Also, it cannot access
caller sensitive methods.
public static <T extends Member> T reflectAs(Class<T> expected, MethodHandle target)
Lookup.revealDirect
on the target to obtain its symbolic reference, and then called
MethodHandleInfo.reflectAs
to resolve the symbolic reference to a member.
If there is a security manager, its checkPermission
method
is called with a ReflectPermission("suppressAccessChecks")
permission.
T
- the desired type of the result, either Member
or a subtypetarget
- a direct method handle to crack into symbolic reference componentsexpected
- a class object representing the desired result type T
SecurityException
- if the caller is not privileged to call setAccessible
NullPointerException
- if either argument is null
IllegalArgumentException
- if the target is not a direct method handleClassCastException
- if the member is not of the expected typepublic static MethodHandle arrayElementGetter(Class<?> arrayClass) throws IllegalArgumentException
int
.arrayClass
- an array typeNullPointerException
- if the argument is nullIllegalArgumentException
- if arrayClass is not an array typepublic static MethodHandle arrayElementSetter(Class<?> arrayClass) throws IllegalArgumentException
arrayClass
- the class of an arrayNullPointerException
- if the argument is nullIllegalArgumentException
- if arrayClass is not an array typepublic static MethodHandle spreadInvoker(MethodType type, int leadingArgCount)
type
, with a given number of trailing arguments replaced by
a single trailing Object[]
array.
The resulting invoker will be a method handle with the following
arguments:
MethodHandle
target
leadingArgCount
)
Object[]
array containing trailing arguments
The invoker will invoke its target like a call to invoke
with
the indicated type
.
That is, if the target is exactly of the given type
, it will behave
like invokeExact
; otherwise it behave as if asType
is used to convert the target to the required type
.
The type of the returned invoker will not be the given type
, but rather
will have all parameters except the first leadingArgCount
replaced by a single array of type Object[]
, which will be
the final parameter.
Before invoking its target, the invoker will spread the final array, apply
reference casts as necessary, and unbox and widen primitive arguments.
If, when the invoker is called, the supplied array argument does
not have the correct number of elements, the invoker will throw
an IllegalArgumentException
instead of invoking the target.
This method is equivalent to the following code (though it may be more efficient):
This method throws no reflective or security exceptions.MethodHandle invoker = MethodHandles.invoker(type); int spreadArgCount = type.parameterCount() - leadingArgCount; invoker = invoker.asSpreader(Object[].class, spreadArgCount); return invoker;
type
- the desired target typeleadingArgCount
- number of fixed arguments, to be passed unchanged to the targetNullPointerException
- if type
is nullIllegalArgumentException
- if leadingArgCount
is not in
the range from 0 to type.parameterCount()
inclusive,
or if the resulting method handle's type would have
too many parameterspublic static MethodHandle exactInvoker(MethodType type)
invokeExact
.
The resulting invoker will have a type which is
exactly equal to the desired type, except that it will accept
an additional leading argument of type MethodHandle
.
This method is equivalent to the following code (though it may be more efficient):
publicLookup().findVirtual(MethodHandle.class, "invokeExact", type)
Discussion:
Invoker method handles can be useful when working with variable method handles
of unknown types.
For example, to emulate an invokeExact
call to a variable method
handle M
, extract its type T
,
look up the invoker method X
for T
,
and call the invoker method, as X.invoke(T, A...)
.
(It would not work to call X.invokeExact
, since the type T
is unknown.)
If spreading, collecting, or other argument transformations are required,
they can be applied once to the invoker X
and reused on many M
method handle values, as long as they are compatible with the type of X
.
(Note: The invoker method is not available via the Core Reflection API.
An attempt to call java.lang.reflect.Method.invoke
on the declared invokeExact
or invoke
method will raise an
UnsupportedOperationException
.)
This method throws no reflective or security exceptions.
type
- the desired target typeIllegalArgumentException
- if the resulting method handle's type would have
too many parameterspublic static MethodHandle invoker(MethodType type)
invoke
.
The resulting invoker will have a type which is
exactly equal to the desired type, except that it will accept
an additional leading argument of type MethodHandle
.
Before invoking its target, if the target differs from the expected type,
the invoker will apply reference casts as
necessary and box, unbox, or widen primitive values, as if by asType
.
Similarly, the return value will be converted as necessary.
If the target is a variable arity method handle,
the required arity conversion will be made, again as if by asType
.
This method is equivalent to the following code (though it may be more efficient):
publicLookup().findVirtual(MethodHandle.class, "invoke", type)
Discussion:
A general method type is one which
mentions only Object
arguments and return values.
An invoker for such a type is capable of calling any method handle
of the same arity as the general type.
(Note: The invoker method is not available via the Core Reflection API.
An attempt to call java.lang.reflect.Method.invoke
on the declared invokeExact
or invoke
method will raise an
UnsupportedOperationException
.)
This method throws no reflective or security exceptions.
type
- the desired target typeIllegalArgumentException
- if the resulting method handle's type would have
too many parameterspublic static MethodHandle explicitCastArguments(MethodHandle target, MethodType newType)
If the original type and new type are equal, returns target.
The same conversions are allowed as for MethodHandle.asType
,
and some additional conversions are also applied if those conversions fail.
Given types T0, T1, one of the following conversions is applied
if possible, before or instead of any conversions done by asType
:
(x & 1) != 0
.
target
- the method handle to invoke after arguments are retypednewType
- the expected type of the new method handleNullPointerException
- if either argument is nullWrongMethodTypeException
- if the conversion cannot be madeMethodHandle.asType(java.lang.invoke.MethodType)
public static MethodHandle permuteArguments(MethodHandle target, MethodType newType, int... reorder)
The given array controls the reordering.
Call #I
the number of incoming parameters (the value
newType.parameterCount()
, and call #O
the number
of outgoing parameters (the value target.type().parameterCount()
).
Then the length of the reordering array must be #O
,
and each element must be a non-negative number less than #I
.
For every N
less than #O
, the N
-th
outgoing argument will be taken from the I
-th incoming
argument, where I
is reorder[N]
.
No argument or return value conversions are applied.
The type of each incoming argument, as determined by newType
,
must be identical to the type of the corresponding outgoing parameter
or parameters in the target method handle.
The return type of newType
must be identical to the return
type of the original target.
The reordering array need not specify an actual permutation.
An incoming argument will be duplicated if its index appears
more than once in the array, and an incoming argument will be dropped
if its index does not appear in the array.
As in the case of dropArguments
,
incoming arguments which are not mentioned in the reordering array
are may be any type, as determined only by newType
.
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodType intfn1 = methodType(int.class, int.class); MethodType intfn2 = methodType(int.class, int.class, int.class); MethodHandle sub = ... (int x, int y) -> (x-y) ...; assert(sub.type().equals(intfn2)); MethodHandle sub1 = permuteArguments(sub, intfn2, 0, 1); MethodHandle rsub = permuteArguments(sub, intfn2, 1, 0); assert((int)rsub.invokeExact(1, 100) == 99); MethodHandle add = ... (int x, int y) -> (x+y) ...; assert(add.type().equals(intfn2)); MethodHandle twice = permuteArguments(add, intfn1, 0, 0); assert(twice.type().equals(intfn1)); assert((int)twice.invokeExact(21) == 42);
target
- the method handle to invoke after arguments are reorderednewType
- the expected type of the new method handlereorder
- an index array which controls the reorderingNullPointerException
- if any argument is nullIllegalArgumentException
- if the index array length is not equal to
the arity of the target, or if any index array element
not a valid index for a parameter of newType
,
or if two corresponding parameter types in
target.type()
and newType
are not identical,public static MethodHandle constant(Class<?> type, Object value)
Before the method handle is returned, the passed-in value is converted to the requested type. If the requested type is primitive, widening primitive conversions are attempted, else reference conversions are attempted.
The returned method handle is equivalent to identity(type).bindTo(value)
.
type
- the return type of the desired method handlevalue
- the value to returnNullPointerException
- if the type
argument is nullClassCastException
- if the value cannot be converted to the required return typeIllegalArgumentException
- if the given type is void.class
public static MethodHandle identity(Class<?> type)
type
- the type of the sole parameter and return value of the desired method handleNullPointerException
- if the argument is nullIllegalArgumentException
- if the given type is void.class
public static MethodHandle insertArguments(MethodHandle target, int pos, Object... values)
The type of the new method handle will drop the types for the bound parameters from the original target type, since the new method handle will no longer require those arguments to be supplied by its callers.
Each given argument object must match the corresponding bound parameter type. If a bound parameter type is a primitive, the argument object must be a wrapper, and will be unboxed to produce the primitive value.
The pos
argument selects which parameters are to be bound.
It may range between zero and N-L (inclusively),
where N is the arity of the target method handle
and L is the length of the values array.
target
- the method handle to invoke after the argument is insertedpos
- where to insert the argument (zero for the first)values
- the series of arguments to insertNullPointerException
- if the target or the values
array is nullMethodHandle.bindTo(java.lang.Object)
public static MethodHandle dropArguments(MethodHandle target, int pos, List<Class<?>> valueTypes)
The pos
argument may range between zero and N,
where N is the arity of the target.
If pos
is zero, the dummy arguments will precede
the target's real arguments; if pos
is N
they will come after.
Example:
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class)); assertEquals("xy", (String) cat.invokeExact("x", "y")); MethodType bigType = cat.type().insertParameterTypes(0, int.class, String.class); MethodHandle d0 = dropArguments(cat, 0, bigType.parameterList().subList(0,2)); assertEquals(bigType, d0.type()); assertEquals("yz", (String) d0.invokeExact(123, "x", "y", "z"));
This method is also equivalent to the following code:
dropArguments
(target, pos, valueTypes.toArray(new Class[0]))
target
- the method handle to invoke after the arguments are droppedvalueTypes
- the type(s) of the argument(s) to droppos
- position of first argument to drop (zero for the leftmost)NullPointerException
- if the target is null,
or if the valueTypes
list or any of its elements is nullIllegalArgumentException
- if any element of valueTypes
is void.class
,
or if pos
is negative or greater than the arity of the target,
or if the new method handle's type would have too many parameterspublic static MethodHandle dropArguments(MethodHandle target, int pos, Class<?>... valueTypes)
The pos
argument may range between zero and N,
where N is the arity of the target.
If pos
is zero, the dummy arguments will precede
the target's real arguments; if pos
is N
they will come after.
Example:
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class)); assertEquals("xy", (String) cat.invokeExact("x", "y")); MethodHandle d0 = dropArguments(cat, 0, String.class); assertEquals("yz", (String) d0.invokeExact("x", "y", "z")); MethodHandle d1 = dropArguments(cat, 1, String.class); assertEquals("xz", (String) d1.invokeExact("x", "y", "z")); MethodHandle d2 = dropArguments(cat, 2, String.class); assertEquals("xy", (String) d2.invokeExact("x", "y", "z")); MethodHandle d12 = dropArguments(cat, 1, int.class, boolean.class); assertEquals("xz", (String) d12.invokeExact("x", 12, true, "z"));
This method is also equivalent to the following code:
dropArguments
(target, pos, Arrays.asList(valueTypes))
target
- the method handle to invoke after the arguments are droppedvalueTypes
- the type(s) of the argument(s) to droppos
- position of first argument to drop (zero for the leftmost)NullPointerException
- if the target is null,
or if the valueTypes
array or any of its elements is nullIllegalArgumentException
- if any element of valueTypes
is void.class
,
or if pos
is negative or greater than the arity of the target,
or if the new method handle's type would have
too many parameterspublic static MethodHandle filterArguments(MethodHandle target, int pos, MethodHandle... filters)
The pre-processing is performed by one or more method handles,
specified in the elements of the filters
array.
The first element of the filter array corresponds to the pos
argument of the target, and so on in sequence.
Null arguments in the array are treated as identity functions, and the corresponding arguments left unchanged. (If there are no non-null elements in the array, the original target is returned.) Each filter is applied to the corresponding argument of the adapter.
If a filter F
applies to the N
th argument of
the target, then F
must be a method handle which
takes exactly one argument. The type of F
's sole argument
replaces the corresponding argument type of the target
in the resulting adapted method handle.
The return type of F
must be identical to the corresponding
parameter type of the target.
It is an error if there are elements of filters
(null or not)
which do not correspond to argument positions in the target.
Example:
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class)); MethodHandle upcase = lookup().findVirtual(String.class, "toUpperCase", methodType(String.class)); assertEquals("xy", (String) cat.invokeExact("x", "y")); MethodHandle f0 = filterArguments(cat, 0, upcase); assertEquals("Xy", (String) f0.invokeExact("x", "y")); // Xy MethodHandle f1 = filterArguments(cat, 1, upcase); assertEquals("xY", (String) f1.invokeExact("x", "y")); // xY MethodHandle f2 = filterArguments(cat, 0, upcase, upcase); assertEquals("XY", (String) f2.invokeExact("x", "y")); // XY
Here is pseudocode for the resulting adapter:
V target(P... p, A[i]... a[i], B... b); A[i] filter[i](V[i]); T adapter(P... p, V[i]... v[i], B... b) { return target(p..., f[i](v[i])..., b...); }
target
- the method handle to invoke after arguments are filteredpos
- the position of the first argument to filterfilters
- method handles to call initially on filtered argumentsNullPointerException
- if the target is null
or if the filters
array is nullIllegalArgumentException
- if a non-null element of filters
does not match a corresponding argument type of target as described above,
or if the pos+filters.length
is greater than target.type().parameterCount()
,
or if the resulting method handle's type would have
too many parameterspublic static MethodHandle collectArguments(MethodHandle target, int pos, MethodHandle filter)
If the filter returns a value, the target must accept that value as
its argument in position pos
, preceded and/or followed by
any arguments not passed to the filter.
If the filter returns void, the target must accept all arguments
not passed to the filter.
No arguments are reordered, and a result returned from the filter
replaces (in order) the whole subsequence of arguments originally
passed to the adapter.
The argument types (if any) of the filter
replace zero or one argument types of the target, at position pos
,
in the resulting adapted method handle.
The return type of the filter (if any) must be identical to the
argument type of the target at position pos
, and that target argument
is supplied by the return value of the filter.
In all cases, pos
must be greater than or equal to zero, and
pos
must also be less than or equal to the target's arity.
Example:
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodHandle deepToString = publicLookup() .findStatic(Arrays.class, "deepToString", methodType(String.class, Object[].class)); MethodHandle ts1 = deepToString.asCollector(String[].class, 1); assertEquals("[strange]", (String) ts1.invokeExact("strange")); MethodHandle ts2 = deepToString.asCollector(String[].class, 2); assertEquals("[up, down]", (String) ts2.invokeExact("up", "down")); MethodHandle ts3 = deepToString.asCollector(String[].class, 3); MethodHandle ts3_ts2 = collectArguments(ts3, 1, ts2); assertEquals("[top, [up, down], strange]", (String) ts3_ts2.invokeExact("top", "up", "down", "strange")); MethodHandle ts3_ts2_ts1 = collectArguments(ts3_ts2, 3, ts1); assertEquals("[top, [up, down], [strange]]", (String) ts3_ts2_ts1.invokeExact("top", "up", "down", "strange")); MethodHandle ts3_ts2_ts3 = collectArguments(ts3_ts2, 1, ts3); assertEquals("[top, [[up, down, strange], charm], bottom]", (String) ts3_ts2_ts3.invokeExact("top", "up", "down", "strange", "charm", "bottom"));
Here is pseudocode for the resulting adapter:
T target(A...,V,C...); V filter(B...); T adapter(A... a,B... b,C... c) { V v = filter(b...); return target(a...,v,c...); } // and if the filter has no arguments: T target2(A...,V,C...); V filter2(); T adapter2(A... a,C... c) { V v = filter2(); return target2(a...,v,c...); } // and if the filter has a void return: T target3(A...,C...); void filter3(B...); void adapter3(A... a,B... b,C... c) { filter3(b...); return target3(a...,c...); }
A collection adapter collectArguments(mh, 0, coll)
is equivalent to
one which first "folds" the affected arguments, and then drops them, in separate
steps as follows:
If the target method handle consumes no arguments besides than the result (if any) of the filtermh = MethodHandles.dropArguments(mh, 1, coll.type().parameterList()); //step 2 mh = MethodHandles.foldArguments(mh, coll); //step 1
coll
, then collectArguments(mh, 0, coll)
is equivalent to filterReturnValue(coll, mh)
.
If the filter method handle coll
consumes one argument and produces
a non-void result, then collectArguments(mh, N, coll)
is equivalent to filterArguments(mh, N, coll)
.
Other equivalences are possible but would require argument permutation.target
- the method handle to invoke after filtering the subsequence of argumentspos
- the position of the first adapter argument to pass to the filter,
and/or the target argument which receives the result of the filterfilter
- method handle to call on the subsequence of argumentsNullPointerException
- if either argument is nullIllegalArgumentException
- if the return type of filter
is non-void and is not the same as the pos
argument of the target,
or if pos
is not between 0 and the target's arity, inclusive,
or if the resulting method handle's type would have
too many parametersfoldArguments(java.lang.invoke.MethodHandle, java.lang.invoke.MethodHandle)
,
filterArguments(java.lang.invoke.MethodHandle, int, java.lang.invoke.MethodHandle...)
,
filterReturnValue(java.lang.invoke.MethodHandle, java.lang.invoke.MethodHandle)
public static MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter)
If the target returns a value, the filter must accept that value as its only argument. If the target returns void, the filter must accept no arguments.
The return type of the filter replaces the return type of the target in the resulting adapted method handle. The argument type of the filter (if any) must be identical to the return type of the target.
Example:
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class)); MethodHandle length = lookup().findVirtual(String.class, "length", methodType(int.class)); System.out.println((String) cat.invokeExact("x", "y")); // xy MethodHandle f0 = filterReturnValue(cat, length); System.out.println((int) f0.invokeExact("x", "y")); // 2
Here is pseudocode for the resulting adapter:
V target(A...); T filter(V); T adapter(A... a) { V v = target(a...); return filter(v); } // and if the target has a void return: void target2(A...); T filter2(); T adapter2(A... a) { target2(a...); return filter2(); } // and if the filter has a void return: V target3(A...); void filter3(V); void adapter3(A... a) { V v = target3(a...); filter3(v); }
target
- the method handle to invoke before filtering the return valuefilter
- method handle to call on the return valueNullPointerException
- if either argument is nullIllegalArgumentException
- if the argument list of filter
does not match the return type of target as described abovepublic static MethodHandle foldArguments(MethodHandle target, MethodHandle combiner)
The pre-processing is performed by combiner
, a second method handle.
Of the arguments passed to the adapter, the first N
arguments
are copied to the combiner, which is then called.
(Here, N
is defined as the parameter count of the combiner.)
After this, control passes to the target, with any result
from the combiner inserted before the original N
incoming
arguments.
If the combiner returns a value, the first parameter type of the target
must be identical with the return type of the combiner, and the next
N
parameter types of the target must exactly match the parameters
of the combiner.
If the combiner has a void return, no result will be inserted,
and the first N
parameter types of the target
must exactly match the parameters of the combiner.
The resulting adapter is the same type as the target, except that the first parameter type is dropped, if it corresponds to the result of the combiner.
(Note that dropArguments
can be used to remove any arguments
that either the combiner or the target does not wish to receive.
If some of the incoming arguments are destined only for the combiner,
consider using asCollector
instead, since those
arguments will not need to be live on the stack on entry to the
target.)
Example:
import static java.lang.invoke.MethodHandles.*; import static java.lang.invoke.MethodType.*; ... MethodHandle trace = publicLookup().findVirtual(java.io.PrintStream.class, "println", methodType(void.class, String.class)) .bindTo(System.out); MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class)); assertEquals("boojum", (String) cat.invokeExact("boo", "jum")); MethodHandle catTrace = foldArguments(cat, trace); // also prints "boo": assertEquals("boojum", (String) catTrace.invokeExact("boo", "jum"));
Here is pseudocode for the resulting adapter:
// there are N arguments in A... T target(V, A[N]..., B...); V combiner(A...); T adapter(A... a, B... b) { V v = combiner(a...); return target(v, a..., b...); } // and if the combiner has a void return: T target2(A[N]..., B...); void combiner2(A...); T adapter2(A... a, B... b) { combiner2(a...); return target2(a..., b...); }
target
- the method handle to invoke after arguments are combinedcombiner
- method handle to call initially on the incoming argumentsNullPointerException
- if either argument is nullIllegalArgumentException
- if combiner
's return type
is non-void and not the same as the first argument type of
the target, or if the initial N
argument types
of the target
(skipping one matching the combiner
's return type)
are not identical with the argument types of combiner
public static MethodHandle guardWithTest(MethodHandle test, MethodHandle target, MethodHandle fallback)
Here is pseudocode for the resulting adapter:
Note that the test arguments (boolean test(A...); T target(A...,B...); T fallback(A...,B...); T adapter(A... a,B... b) { if (test(a...)) return target(a..., b...); else return fallback(a..., b...); }
a...
in the pseudocode) cannot
be modified by execution of the test, and so are passed unchanged
from the caller to the target or fallback as appropriate.test
- method handle used for test, must return booleantarget
- method handle to call if test passesfallback
- method handle to call if test failsNullPointerException
- if any argument is nullIllegalArgumentException
- if test
does not return boolean,
or if all three method types do not match (with the return
type of test
changed to match that of the target).public static MethodHandle catchException(MethodHandle target, Class<? extends Throwable> exType, MethodHandle handler)
The target and handler must have the same corresponding
argument and return types, except that handler may omit trailing arguments
(similarly to the predicate in guardWithTest
).
Also, the handler must have an extra leading parameter of exType
or a supertype.
Here is pseudocode for the resulting adapter:
Note that the saved arguments (T target(A..., B...); T handler(ExType, A...); T adapter(A... a, B... b) { try { return target(a..., b...); } catch (ExType ex) { return handler(ex, a...); } }
a...
in the pseudocode) cannot
be modified by execution of the target, and so are passed unchanged
from the caller to the handler, if the handler is invoked.
The target and handler must return the same type, even if the handler
always throws. (This might happen, for instance, because the handler
is simulating a finally
clause).
To create such a throwing handler, compose the handler creation logic
with throwException
,
in order to create a method handle of the correct return type.
target
- method handle to callexType
- the type of exception which the handler will catchhandler
- method handle to call if a matching exception is thrownNullPointerException
- if any argument is nullIllegalArgumentException
- if handler
does not accept
the given exception type, or if the method handle types do
not match in their return types and their
corresponding parameterspublic static MethodHandle throwException(Class<?> returnType, Class<? extends Throwable> exType)
exType
.
The method handle will accept a single argument of exType
,
and immediately throw it as an exception.
The method type will nominally specify a return of returnType
.
The return type may be anything convenient: It doesn't matter to the
method handle's behavior, since it will never return normally.returnType
- the return type of the desired method handleexType
- the parameter type of the desired method handleNullPointerException
- if either argument is nullDracula Javadoc Sample, Made with Allan Im.


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Comparison with other software¶
pyGPGO is not the only available Python package for bayesian optimization. To the best of our knowledge, we believe that it is one of the most comprehensive ones in terms of features available to the user. We show a table comparing some of the most common features here:
| pyGPGO | Spearmint | fmfn/BayesianOptimization | pyBO | MOE | GPyOpt | scikit-optimize | |
|---|---|---|---|---|---|---|---|
| GP implementation | Native | Native | via scikit-learn | via Reggie | Native | via GPy | via scikit-learn |
| Modular | Yes | No | No | No | No | Yes | No |
| Surrogates | {GP, tSP, RF, ET, GBM} | {GP} | {GP} | {GP} | {GP} | {GP, RF, WGP} | {GP, RF, GBM} |
| Type II ML optimization | Yes | No | No | No | Yes | Yes | Yes |
| MCMC inference | Yes (via pyMC3) | Yes | No | Yes | No | Yes | No |
| Choice of MCMC sampler | Yes | Yes | No | Yes | No | No | No |
| Acquisition functions | {PI, EI, UCB, Entropy} | {EI} | {PI, EI, UCB} | {PI, EI, UCB, Thompson sampling} | {EI} | {PI, EI, UCB} | {PI, EI, UCB} |
| Integrated acq. function | Yes | Yes | No | Yes | No | Yes | No |
| License | MIT | Academic | MIT | BSD-2 | Apache | BSD-3 | BSD |
| Last update (as of Apr. 2017) | Apr 2016 | Mar 2017 | Sept 2015 | Apr 2016 | Apr 2017 | Apr 2017 | |
| Python version | > 3.5 | 2.7 | 2/3 | 2/3 | 2.7 | 2/3 | 2/3 |
If you like some other feature implemented into pyGPGO or think this table is outdated or incorrect, please let us know by opening an issue on the Github repository of the package!