list.sort() not sorting values correctly by second tuple parameter
<p>I am trying to sort a list of tuples by the second parameter in the tuple in Python 3.5.2 to find which algorithms take the <code>least -&gt; most</code> time in ascending order, however for some reason the looks to be sorting by random. My code:</p>

<pre><code>import math

def speeds(n):

    new_dictionary = {}

    six_n_log_n = 6 * n * math.log(n, 2)
    thr_n_exp05 = 3 * (n ** 0.5)
    four_expn = 4 ** n
    ceil_sqrt_n = math.ceil(math.sqrt(n))
    five_n = 5 * n
    n_cubed = n ** 3
    log_log_n = math.log(math.log(n, 2))
    n_exp_01 = n ** 0.01
    floor_2_n_log_exp2_n = math.floor(2 * n * (math.log(n, 2)**2))
    n_exp2_log_n = (n ** 2) * math.log(n, 2)
    log_exp2_n = math.log(n, 2) ** 2
    one_div_n = 1 / n
    two_exp_n = 2 ** n
    four_exp_logn = 4 ** (math.log(n, 2))
    two_exp_logn = 2 ** (math.log(n, 2))
    four_n_exp_threehalves = 4 * (n ** (3/2))
    n_exp2 = n ** 2
    sqrt_log_n = math.sqrt(math.log(n, 2))

    new_dictionary[0] = six_n_log_n
    new_dictionary[1] = thr_n_exp05
    new_dictionary[2] = four_expn
    new_dictionary[3] = ceil_sqrt_n
    new_dictionary[4] = five_n
    new_dictionary[5] = n_cubed
    new_dictionary[6] = log_log_n
    new_dictionary[7] = n_exp_01
    new_dictionary[8] = floor_2_n_log_exp2_n
    new_dictionary[9] = n_exp2_log_n
    new_dictionary[10] = log_exp2_n
    new_dictionary[11] = one_div_n
    new_dictionary[12] = two_exp_n
    new_dictionary[13] = four_exp_logn
    new_dictionary[14] = two_exp_logn
    new_dictionary[15] = four_n_exp_threehalves
    new_dictionary[16] = n_exp2
    new_dictionary[17] = sqrt_log_n

    sorted_list = []
    for key in new_dictionary:
        sorted_list.append((key, new_dictionary[key]))

    sorted_list.sort(key=lambda x: x[1])

    for i, x in sorted_list:
        print(sorted_list[i])

    return sorted_list

n = 15
speeds(n)
</code></pre>

<p>The expected output should be tuples in ascending order by the second parameter, but instead, I receive this:</p>

<pre><code>(15, 232.379000772445)
(10, 15.263794126054286)
(14, 15.000000000000002)
(2, 1073741824)
(17, 1.9765855902562173)
(7, 1.027450511266727)
(9, 879.0503840119167)
(13, 225.00000000000006)
(3, 4)
(12, 32768)
(8, 457)
(5, 3375)
(11, 0.06666666666666667)
(4, 75)
(16, 225)
(1, 11.618950038622252)
(0, 351.6201536047667)
(6, 1.3627418135330593)
</code></pre>

<p>Can anyone tell me why I'm getting a seemingly random order from this? Can't seem to find where my problem is.</p>

<p>When you iterate over your tuples, you want to print the <em>tuple</em> itself:</p>

<pre><code>for tup in sorted_list:
    print(tup)
</code></pre>

<p>otherwise, you are printing the values at the index based on the <em>first value</em> of the index. For example, the first value in the sorted list is:</p>

<pre><code>(11, 0)
</code></pre>

<p>is actually looking for:</p>

<pre><code>sorted_list[11]
</code></pre>

<p>which is why you see the improper first value.</p>

python python-3.x sorting tuples