# `cedd` — auto-generated data guide

> Auto-generated on 2026-10-08T15:45:30+08:00 by `scripts/generate_processed_readmes.py` from the files actually present in this directory. Do not edit by hand — re-run the generator (or `scripts/flatten_hko_data.py`) after the data changes.

## Overview

- **Files:** 2
- **Total rows:** 98,730
- **Total size:** 149.3 KB
- **Sources:** cedd_geo
- **Time coverage:** 2023-01-01 00:00:00 .. 2025-12-31 00:00:00
- **Join keys:** use `station_id` / `station_code` to join to the station metadata table in this or the `hko` section; use the time column shown per file for temporal joins.

## Files

### `cedd_daily_rainfall.parquet`

- **Format:** parquet · **Rows:** 98,640 · **Columns:** 10 · **Size:** 145.9 KB
- **Purpose:** HKO CIS daily total rainfall
- **Source:** cedd_geo
- **Time coverage (`date`):** 2023-01-01 00:00:00 .. 2025-12-31 00:00:00
- **station_id:** 90 distinct

| Column | Type | Non-null | Range / values | Description |
|---|---|---|---|---|
| `date` | str | 98640/98640 (100%) | 2023-01-01 00:00:00 .. 2025-12-31 00:00:00 | observation date |
| `station_id` | str | 98640/98640 (100%) | 90 distinct; e.g. "H01" | AWS/CoWIN station identifier |
| `station_name` | str | 98640/98640 (100%) | 61 distinct; e.g. "Mount Davis" | station name |
| `easting` | int64 | 98640/98640 (100%) | range 804276 .. 855431 | field |
| `northing` | int64 | 98640/98640 (100%) | range 802763 .. 842003 | field |
| `value_raw` | str | 98640/98640 (100%) | 676 distinct; e.g. "0" | original value exactly as received (may be 'M' or 'Trace') |
| `rain_mm_1d` | float64 | 97692/98640 (99%) | range 0 .. 622.5 | daily total rainfall (mm) |
| `is_trace` | bool | 98640/98640 (100%) | True / False | TRUE when the raw rainfall value is 'Trace' (< 0.05 mm) |
| `is_incomplete` | bool | 98640/98640 (100%) | True / False | field |
| `source` | str | 98640/98640 (100%) | values: cedd_geo | source dataset identifier |

### `cedd_stations.csv`

- **Format:** CSV · **Rows:** 90 · **Columns:** 5 · **Size:** 3.4 KB
- **Purpose:** HKO station metadata
- **Source:** cedd_geo
- **station_id:** 90 distinct

| Column | Type | Non-null | Range / values | Description |
|---|---|---|---|---|
| `station_id` | str | 90/90 (100%) | 90 distinct; e.g. "H01" | AWS/CoWIN station identifier |
| `station_name` | str | 90/90 (100%) | 61 distinct; e.g. "Mount Davis" | station name |
| `easting` | int64 | 90/90 (100%) | range 804276 .. 855431 | field |
| `northing` | int64 | 90/90 (100%) | range 802763 .. 842003 | field |
| `source` | str | 90/90 (100%) | values: cedd_geo | source dataset identifier |