30-seconds-of-code/website/app/templates/index.html

{% extends "base.html" %}

{% block content %}<div class="row" style="height:calc(100vh - 5.875rem);overflow:hidden"><input id="doc-drawer-checkbox" class="drawer" value="on" type="checkbox"><nav class="col-md-4 col-lg-3" style="border-top:0"><div class="group"><input class="search" id="searchInput" onkeyup="search(this)" type="text"><label id="search-label">Search for snippet...</label></div><label for="doc-drawer-checkbox" class="button drawer-close"></label><h3 style = "">Math</h3><a class="sublink-1" tags="math" href="#average" style="">average</a><a class="sublink-1" tags="math" href="#factorial" style="">factorial</a><a class="sublink-1" tags="math" href="#gcd" style="">gcd</a><a class="sublink-1" tags="math" href="#lcm" style="">lcm</a><a class="sublink-1" tags="math" href="#max_n" style="">max_n</a><a class="sublink-1" tags="math" href="#min_n" style="">min_n</a><h3 style = "">List</h3><a class="sublink-1" tags="list" href="#chunk" style="">chunk</a><a class="sublink-1" tags="list" href="#compact" style="">compact</a><a class="sublink-1" tags="list" href="#count_occurences" style="">count_occurences</a><a class="sublink-1" tags="list" href="#deep_flatten" style="">deep_flatten</a><a class="sublink-1" tags="list" href="#difference" style="">difference</a><a class="sublink-1" tags="list" href="#shuffle" style="">shuffle</a><a class="sublink-1" tags="list" href="#spread" style="">spread</a><a class="sublink-1" tags="list" href="#zip" style="">zip</a><a class="sublink-1" tags="list" href="#count_by" style="">count_by</a><a class="sublink-1" tags="list" href="#difference_by" style="">difference_by</a><a class="sublink-1" tags="list" href="#insertion_sort" style="">insertion_sort</a><a class="sublink-1" tags="list" href="#bubble_sort" style="">bubble_sort</a><a class="sublink-1" tags="list" href="#has_duplicates" style="">has_duplicates</a><h3 style = "">String</h3><a class="sublink-1" tags="string" href="#count_vowels" style="">count_vowels</a><a class="sublink-1" tags="string" href="#byte_size" style="">byte_size</a><a class="sublink-1" tags="string" href="#capitalize" style="">capitalize</a><a class="sublink-1" tags="string" href="#capitalize_every_word" style="">capitalize_every_word</a><a class="sublink-1" tags="string" href="#decapitalize" style="">decapitalize</a><a class="sublink-1" tags="string" href="#palindrome" style="">palindrome</a><a class="sublink-1" tags="string" href="#is_upper_case" style="">is_upper_case</a><a class="sublink-1" tags="string" href="#is_lower_case" style="">is_lower_case</a><h3 style = "">Object</h3><a class="sublink-1" tags="object" href="#keys_only" style="">keys_only</a><a class="sublink-1" tags="object" href="#values_only" style="">values_only</a><a class="sublink-1" tags="object" href="#all_unique" style="">all_unique</a></nav><main class="col-sm-12 col-md-8 col-lg-9" style="height:100%;overflow-y:auto;background:#eceef2;padding:0"><a id="top"></a><h2 style="text-align:center">Math</h2><div class="card fluid"><h3 id="average" class="section double-padded">average</h3><!--<form action="" method="post"><button type="submit" value="average" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p><emoji>ℹ</emoji> Already implemented via <code>statistics.mean</code>. <code>statistics.mean</code> takes an array as an argument whereas this function takes variadic arguments.</p>
<p>Returns the average of two or more numbers.</p>
<p>Takes the sum of all the <code>args</code> and divides it by <code>len(args)</code>. The second argument <code>0.0</code> in sum is to handle floating point division in <code>python3</code>.</p>

<pre class="language-python">def average(*args):
    return sum(args, 0.0) / len(args)</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">average(*[1, 2, 3]) # 2.0
average(1, 2, 3) # 2.0</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="factorial" class="section double-padded">factorial</h3><!--<form action="" method="post"><button type="submit" value="factorial" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Calculates the factorial of a number.</p>
<p>Use recursion. If <code>num</code> is less than or equal to <code>1</code>, return <code>1</code>. Otherwise, return the product of <code>num</code> and the factorial of <code>num - 1</code>. Throws an exception if <code>num</code> is a negative or a floating point number.</p>

<pre class="language-python">def factorial(num):
    if not ((num &gt;= 0) &amp; (num % 1 == 0)):
        raise Exception(
            f"Number( {num} ) can't be floating point or negative ")
    return 1 if num == 0 else num * factorial(num - 1)</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">factorial(6) # 720</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="gcd" class="section double-padded">gcd</h3><!--<form action="" method="post"><button type="submit" value="gcd" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p><emoji>ℹ</emoji> <code>math.gcd</code> works with only two numbers</p>
<p>Calculates the greatest common divisor between two or more numbers/lists.</p>
<p>The <code>helperGcdfunction</code> uses recursion. Base case is when <code>y</code> equals <code>0</code>. In this case, return <code>x</code>. Otherwise, return the GCD of <code>y</code> and the remainder of the division <code>x/y</code>.</p>
<p>Uses the reduce function from the inbuilt module <code>functools</code>. Also defines a method <code>spread</code> for javascript like spreading of lists.</p>

<pre class="language-python">from functools import reduce


def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret


def gcd(*args):
    numbers = []
    numbers.extend(spread(list(args)))

    def _gcd(x, y):
        return x if not y else gcd(y, x % y)

    return reduce((lambda x, y: _gcd(x, y)), numbers)</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">gcd(8,36) # 4</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="lcm" class="section double-padded">lcm</h3><!--<form action="" method="post"><button type="submit" value="lcm" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns the least common multiple of two or more numbers.</p>
<p>Use the <code>greatest common divisor (GCD)</code> formula and the fact that <code>lcm(x,y) = x * y / gcd(x,y)</code> to determine the least common multiple. The GCD formula uses recursion.</p>
<p>Uses <code>reduce</code> function from the inbuilt module <code>functools</code>. Also defines a method <code>spread</code> for javascript like spreading of lists.</p>

<pre class="language-python">from functools import reduce


def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret


def lcm(*args):
    numbers = []
    numbers.extend(spread(list(args)))

    def _gcd(x, y):
        return x if not y else _gcd(y, x % y)

    def _lcm(x, y):
        return x * y / _gcd(x, y)

    return reduce((lambda x, y: _lcm(x, y)), numbers)</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">lcm(12, 7) # 84
lcm([1, 3, 4], 5) # 60</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="max_n" class="section double-padded">max_n</h3><!--<form action="" method="post"><button type="submit" value="max_n" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns the <code>n</code> maximum elements from the provided list. If <code>n</code> is greater than or equal to the provided list's length, then return the original list(sorted in descending order).</p>
<p>Use <code>list.sort()</code> combined with the <code>deepcopy</code> function from the inbuilt <code>copy</code> module to create a shallow clone of the list and sort it in ascending order and then use <code>list.reverse()</code> reverse it to make it descending order. Use <code>[:n]</code> to get the specified number of elements. Omit the second argument, <code>n</code>, to get a one-element list</p>

<pre class="language-python">def max_n(lst, n=1, reverse=True):
    return sorted(lst, reverse=reverse)[:n]</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">max_n([1, 2, 3]) # [3]
max_n([1, 2, 3], 2) # [3,2]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="min_n" class="section double-padded">min_n</h3><!--<form action="" method="post"><button type="submit" value="min_n" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns the <code>n</code> minimum elements from the provided list. If <code>n</code> is greater than or equal to the provided list's length, then return the original list(sorted in ascending order).</p>
<p>Use <code>list.sort()</code> combined with the <code>deepcopy</code> function from the inbuilt <code>copy</code> module to create a shallow clone of the list and sort it in ascending order. Use <code>[:n]</code> to get the specified number of elements. Omit the second argument, <code>n</code>, to get a one-element list</p>

<pre class="language-python">from copy import deepcopy


def min_n(lst, n=1):
    numbers = deepcopy(lst)
    numbers.sort()
    return numbers[:n]</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">min_n([1, 2, 3]) # [1]
min_n([1, 2, 3], 2) # [1,2]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><h2 style="text-align:center">List</h2><div class="card fluid"><h3 id="chunk" class="section double-padded">chunk</h3><!--<form action="" method="post"><button type="submit" value="chunk" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Chunks an list into smaller lists of a specified size.</p>
<p>Uses <code>range</code> to create a list of desired size. Then use <code>map</code> on this list and fill it with splices of <code>lst</code>.</p>

<pre class="language-python">from math import ceil


def chunk(lst, size):
    return list(
        map(lambda x: lst[x * size:x * size + size],
            list(range(0, ceil(len(lst) / size)))))</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">chunk([1,2,3,4,5],2) # [[1,2],[3,4],5]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="compact" class="section double-padded">compact</h3><!--<form action="" method="post"><button type="submit" value="compact" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Removes falsey values from a list.</p>
<p>Use <code>filter()</code> to filter out falsey values (False, None, 0, and "").</p>

<pre class="language-python">def compact(lst):
    return list(filter(bool, lst))</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">compact([0, 1, False, 2, '', 3, 'a', 's', 34]) # [ 1, 2, 3, 'a', 's', 34 ]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="count_occurences" class="section double-padded">count_occurences</h3><!--<form action="" method="post"><button type="submit" value="count_occurences" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p><emoji>ℹ</emoji> Already implemented via <code>list.count()</code>.</p>
<p>Counts the occurrences of a value in an list.</p>
<p>Uses the list comprehension to increment a counter each time you encounter the specific value inside the list.</p>

<pre class="language-python">def count_occurrences(lst, val):
    return len([x for x in lst if x == val and type(x) == type(val)])</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">count_occurrences([1, 1, 2, 1, 2, 3], 1) # 3</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="deep_flatten" class="section double-padded">deep_flatten</h3><!--<form action="" method="post"><button type="submit" value="deep_flatten" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Deep flattens a list.</p>
<p>Use recursion. Use <code>list.extend()</code> with an empty list (<code>result</code>) and the spread function to flatten a list. Recursively flatten each element that is a list.</p>

<pre class="language-python">def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret


def deep_flatten(lst):
    result = []
    result.extend(
        spread(list(map(lambda x: deep_flatten(x) if type(x) == list else x, lst))))
    return result</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">deep_flatten([1, [2], [[3], 4], 5]) # [1,2,3,4,5]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="difference" class="section double-padded">difference</h3><!--<form action="" method="post"><button type="submit" value="difference" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns the difference between two iterables.</p>
<p>Use list comprehension to only keep values not contained in <code>b</code></p>

<pre class="language-python">def difference(a, b):
    return [item for item in a if item not in b]</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">difference([1, 2, 3], [1, 2, 4]) # [3]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="shuffle" class="section double-padded">shuffle</h3><!--<form action="" method="post"><button type="submit" value="shuffle" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p><emoji>ℹ</emoji> The same algorithm is already implemented via <code>random.shuffle</code>.</p>
<p>Randomizes the order of the values of an list, returning a new list.</p>
<p>Uses the <a href="https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle">Fisher-Yates algorithm</a> to reorder the elements of the list.</p>

<pre class="language-python">from copy import deepcopy
from random import randint


def shuffle(lst):
    temp_lst = deepcopy(lst)
    m = len(temp_lst)
    while (m):
        m -= 1
        i = randint(0, m)
        temp_lst[m], temp_lst[i] = temp_lst[i], temp_lst[m]
    return temp_lst</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">foo = [1,2,3]
shuffle(foo) # [2,3,1] , foo = [1,2,3]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="spread" class="section double-padded">spread</h3><!--<form action="" method="post"><button type="submit" value="spread" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Implements javascript's <code>[].concat(...arr)</code>. Flattens the list(non-deep) and returns an list.</p>

<pre class="language-python">def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">spread([1,2,3,[4,5,6],[7],8,9]) # [1,2,3,4,5,6,7,8,9]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="zip" class="section double-padded">zip</h3><!--<form action="" method="post"><button type="submit" value="zip" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p><emoji>ℹ</emoji> Already implemented via <code>itertools.zip_longest()</code></p>
<p>Creates a list of elements, grouped based on the position in the original lists.</p>
<p>Use <code>max</code> combined with <code>list comprehension</code> to get the length of the longest list in the arguments. Loops for <code>max_length</code> times grouping elements. If lengths of <code>lists</code> vary <code>fill_value</code> is used. By default <code>fill_value</code> is <code>None</code>.</p>

<pre class="language-python">def zip(*args, fillvalue=None):
    max_length = max([len(lst) for lst in args])
    result = []
    for i in range(max_length):
        result.append([
            args[k][i] if i &lt; len(args[k]) else None for k in range(len(args))
        ])
    return result</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">zip(['a', 'b'], [1, 2], [True, False]) # [['a', 1, True], ['b', 2, False]]
zip(['a'], [1, 2], [True, False]) # [['a', 1, True], [None, 2, False]]
zip(['a'], [1, 2], [True, False], fill_value = '_') # [['a', 1, True], ['_', 2, False]]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="count_by" class="section double-padded">count_by</h3><!--<form action="" method="post"><button type="submit" value="count_by" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p><emoji>ℹ</emoji> Already implemented via <code>collections.Counter</code></p>
<p>Groups the elements of a list based on the given function and returns the count of elements in each group.</p>
<p>Use <code>map()</code> to map the values of the list using the given function. Iterate over the map and increase the the elements count each time it occurs.</p>

<pre class="language-python">def count_by(arr, fn=lambda x: x):
    key = {}
    for el in map(fn, arr):
        key[el] = 0 if el not in key else key[el]
        key[el] += 1
    return key</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">from math import floor
count_by([6.1, 4.2, 6.3], floor) # {4: 1, 6: 2}
count_by(['one', 'two', 'three'], len) # {3: 2, 5: 1}</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="difference_by" class="section double-padded">difference_by</h3><!--<form action="" method="post"><button type="submit" value="difference_by" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns the difference between two list, after applying the provided function to each list element of both.</p>
<p>Create a <code>set</code> by applying <code>fn</code> to each element in <code>b</code>, then use list comprehension in combination with fn on a to only keep values not contained in the previously created <code>set</code>.</p>

<pre class="language-python">def difference_by(a, b, fn):
    b = set(map(fn, b))
    return [item for item in a if fn(item) not in b]</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">from math import floor
difference_by([2.1, 1.2], [2.3, 3.4],floor) # [1.2]
difference_by([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], lambda v : v['x']) # [ { x: 2 } ]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="insertion_sort" class="section double-padded">insertion_sort</h3><!--<form action="" method="post"><button type="submit" value="insertion_sort" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>On a very basic level, an insertion sort algorithm contains the logic of shifting around and inserting elements in order to sort an unordered list of any size. The way that it goes about inserting elements, however, is what makes insertion sort so very interesting!</p>

<pre class="language-python">def insertion_sort(lst):

    for i in range(1, len(lst)):
        key = lst[i]
        j = i - 1
        while j &gt;= 0 and key &lt; lst[j]:
            lst[j + 1] = lst[j]
            j -= 1
            lst[j + 1] = key</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">lst = [7,4,9,2,6,3]
insertionsort(lst)
print('Sorted %s'  %lst) # sorted [2, 3, 4, 6, 7, 9]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="bubble_sort" class="section double-padded">bubble_sort</h3><!--<form action="" method="post"><button type="submit" value="bubble_sort" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Bubble_sort uses the technique of comparing and swapping</p>

<pre class="language-python">def bubble_sort(lst):
    for passnum in range(len(lst) - 1, 0, -1):
        for i in range(passnum):
            if lst[i] &gt; lst[i + 1]:
                temp = lst[i]
                lst[i] = lst[i + 1]
                lst[i + 1] = temp</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">lst = [54,26,93,17,77,31,44,55,20]
bubble_sort(lst)
print("sorted %s" %lst) # [17,20,26,31,44,54,55,77,91]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="has_duplicates" class="section double-padded">has_duplicates</h3><!--<form action="" method="post"><button type="submit" value="has_duplicates" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Checks a flat list for duplicate values. Returns True if duplicate values exist and False if values are all unique.</p>
<p>This function compares the length of the list with length of the set() of the list. set() removes duplicate values from the list.</p>

<pre class="language-python">def has_duplicates(lst):
    return len(lst) != len(set(lst))</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">x = [1,2,3,4,5,5]
y = [1,2,3,4,5]
has_duplicates(x) # True
has_duplicates(y) # False</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><h2 style="text-align:center">String</h2><div class="card fluid"><h3 id="count_vowels" class="section double-padded">count_vowels</h3><!--<form action="" method="post"><button type="submit" value="count_vowels" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Retuns <code>number</code> of vowels in provided <code>string</code>.</p>
<p>Use a regular expression to count the number of vowels <code>(A, E, I, O, U)</code> in a string.</p>

<pre class="language-python">import re


def count_vowels(str):
    return len(len(re.findall(r'[aeiou]', str, re.IGNORECASE)))</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">count_vowels('foobar') # 3
count_vowels('gym') # 0</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="byte_size" class="section double-padded">byte_size</h3><!--<form action="" method="post"><button type="submit" value="byte_size" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns the length of a string in bytes.</p>
<p><code>utf-8</code> encodes a given string and find its length.</p>

<pre class="language-python">def byte_size(string):
    return(len(string.encode('utf-8')))</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">byte_size('😀') # 4
byte_size('Hello World') # 11</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="capitalize" class="section double-padded">capitalize</h3><!--<form action="" method="post"><button type="submit" value="capitalize" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Capitalizes the first letter of a string.</p>
<p>Capitalizes the fist letter of the sring and then adds it with rest of the string. Omit the <code>lower_rest</code> parameter to keep the rest of the string intact, or set it to <code>true</code> to convert to lowercase.</p>

<pre class="language-python">def capitalize(string, lower_rest=False):
    return string[:1].upper() + (string[1:].lower() if lower_rest else string[1:])</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">capitalize('fooBar') # 'FooBar'
capitalize('fooBar', True) # 'Foobar'</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="capitalize_every_word" class="section double-padded">capitalize_every_word</h3><!--<form action="" method="post"><button type="submit" value="capitalize_every_word" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Capitalizes the first letter of every word in a string.</p>
<p>Uses <code>str.title</code> to capitalize first letter of evry word in the string.</p>

<pre class="language-python">def capitalize_every_word(string):
    return string.title()</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">capitalize_every_word('hello world!') # 'Hello World!'</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="decapitalize" class="section double-padded">decapitalize</h3><!--<form action="" method="post"><button type="submit" value="decapitalize" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Decapitalizes the first letter of a string.</p>
<p>Decapitalizes the fist letter of the sring and then adds it with rest of the string. Omit the <code>upper_rest</code> parameter to keep the rest of the string intact, or set it to <code>true</code> to convert to uppercase.</p>

<pre class="language-python">def decapitalize(string, upper_rest=False):
    return str[:1].lower() + (str[1:].upper() if upper_rest else str[1:])</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">decapitalize('FooBar') # 'fooBar'
decapitalize('FooBar', True) # 'fOOBAR'</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="palindrome" class="section double-padded">palindrome</h3><!--<form action="" method="post"><button type="submit" value="palindrome" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Returns <code>True</code> if the given string is a palindrome, <code>False</code> otherwise.</p>
<p>Convert string <code>str.lower()</code> and use <code>re.sub</code> to remove non-alphanumeric characters from it. Then compare the new string to the reversed.</p>

<pre class="language-python">def palindrome(string):
    from re import sub
    s = sub('[\W_]', '', string.lower())
    return s == s[::-1]</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">palindrome('taco cat') # True</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="is_upper_case" class="section double-padded">is_upper_case</h3><!--<form action="" method="post"><button type="submit" value="is_upper_case" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Checks if a string is upper case.</p>
<p>Convert the given string to upper case, using <code>str.upper()</code> method and compare it to the original.</p>

<pre class="language-python">def is_upper_case(string):
    return string == string.upper()</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">is_upper_case('ABC') # True
is_upper_case('a3@$') # True
is_upper_case('aB4') # False</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="is_lower_case" class="section double-padded">is_lower_case</h3><!--<form action="" method="post"><button type="submit" value="is_lower_case" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Checks if a string is lower case.</p>
<p>Convert the given string to lower case, using <code>str.lower()</code> method and compare it to the original.</p>

<pre class="language-python">def is_lower_case(string):
    return string == string.lower()</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">is_lower_case('abc') # True
is_lower_case('a3@$') # True
is_lower_case('Ab4') # False</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><h2 style="text-align:center">Object</h2><div class="card fluid"><h3 id="keys_only" class="section double-padded">keys_only</h3><!--<form action="" method="post"><button type="submit" value="keys_only" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Function which accepts a dictionary of key value pairs and returns a new flat list of only the keys.</p>
<p>Uses the .items() function with a for loop on the dictionary to track both the key and value and returns a new list by appending the keys to it. Best used on 1 level-deep key:value pair dictionaries (a flat dictionary) and not nested data-structures which are also commonly used with dictionaries. (a flat dictionary resembles a json and a flat list an array for javascript people).</p>

<pre class="language-python">def keys_only(flat_dict):
    lst = []
    for k, v in flat_dict.items():
        lst.append(k)
    return lst</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">ages = {
     "Peter": 10,
     "Isabel": 11,
     "Anna": 9,
}
keys_only(ages) # ['Peter', 'Isabel', 'Anna']</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="values_only" class="section double-padded">values_only</h3><!--<form action="" method="post"><button type="submit" value="values_only" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Function which accepts a dictionary of key value pairs and returns a new flat list of only the values.</p>
<p>Uses the .items() function with a for loop on the dictionary to track both the key and value of the iteration and returns a new list by appending the values to it. Best used on 1 level-deep key:value pair dictionaries and not nested data-structures.</p>

<pre class="language-python">def values_only(dict):
    lst = []
    for k, v in dict.items():
        lst.append(v)
    return lst</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">ages = {
     "Peter": 10,
     "Isabel": 11,
     "Anna": 9,
}
values_only(ages) # [10, 11, 9]</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><div class="card fluid"><h3 id="all_unique" class="section double-padded">all_unique</h3><!--<form action="" method="post"><button type="submit" value="all_unique" name="submit">Vote</button></form><p></p>--><div class="section double-padded">
<p>Checks a flat list for all unique values. Returns True if list values are all unique and False if list values aren't all unique.</p>
<p>This function compares the length of the list with length of the set() of the list. set() removes duplicate values from the list.</p>

<pre class="language-python">def all_unique(lst):
    return len(lst) == len(set(lst))</pre>
<label class="collapse">Show examples</label>
<pre class="language-python">x = [1,2,3,4,5,6]
y = [1,2,2,3,4,5]
all_unique(x) # True
all_unique(y) # False</pre>
<button class="primary clipboard-copy">📋&nbsp;Copy to clipboard</button></div>

</div><button class="scroll-to-top">↑</button>
			<footer><p style="display:inline-block"><strong>30 seconds of python code</strong> is licensed under the <a href="https://github.com/kriadmin/30-seconds-of-python-code/blob/master/LICENSE">GPL-3.0</a> license.<br>Icons made by <a href="https://www.flaticon.com/authors/smashicons">Smashicons</a> from <a href="https://www.flaticon.com/">www.flaticon.com</a> is licensed by <a href="http://creativecommons.org/licenses/by/3.0/">CC 3.0 BY</a>.<br>Ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> is licensed by <a href="https://opensource.org/licenses/MIT">The MIT License</a><br>Built with the <a href="https://minicss.org">mini.css framework</a>.</p></footer>
			</main></div>{% endblock %}