Python program to find N largest elements from a list

In this example, we will see how to find the N largest elements from a List. The list is the most versatile datatype available in Python, which can be written as a list of comma-separated values (items) between square brackets. Important thing about a list is that the items in a list need not be of the same type

Let?s say the following is the input list ?

[25, 18, 29, 87, 45, 67, 98, 5, 59]

The following is the output displaying the N largest element from the list. Here, N = 3 ?

[98, 87, 67]<b>
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Python program to find N largest elements from a list with for loop

We will use a for loop here to find the N largest elements from a List ?

Example

<div class="execute"></div><div class="code-mirror  language-python" contenteditable="plaintext-only" spellcheck="false" style="outline: none; overflow-wrap: break-word; overflow-y: auto; white-space: pre-wrap;"><span class="token keyword">def</span> <span class="token function">LargestFunc</span><span class="token punctuation">(</span>list1<span class="token punctuation">,</span> N<span class="token punctuation">)</span><span class="token punctuation">:</span>
	new_list <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>
	<span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">0</span><span class="token punctuation">,</span> N<span class="token punctuation">)</span><span class="token punctuation">:</span>
		max1 <span class="token operator">=</span> <span class="token number">0</span>
		<span class="token keyword">for</span> j <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token builtin">len</span><span class="token punctuation">(</span>list1<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">:</span>
			<span class="token keyword">if</span> list1<span class="token punctuation">[</span>j<span class="token punctuation">]</span> <span class="token operator">></span> max1<span class="token punctuation">:</span>
				max1 <span class="token operator">=</span> list1<span class="token punctuation">[</span>j<span class="token punctuation">]</span><span class="token punctuation">;</span>
			
		list1<span class="token punctuation">.</span>remove<span class="token punctuation">(</span>max1<span class="token punctuation">)</span><span class="token punctuation">;</span>
		new_list<span class="token punctuation">.</span>append<span class="token punctuation">(</span>max1<span class="token punctuation">)</span>
	<span class="token keyword">print</span><span class="token punctuation">(</span><span class="token string">"Largest numbers = "</span><span class="token punctuation">,</span>new_list<span class="token punctuation">)</span>

<span class="token comment"># Driver code</span>
my_list <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token number">12</span><span class="token punctuation">,</span> <span class="token number">61</span><span class="token punctuation">,</span> <span class="token number">41</span><span class="token punctuation">,</span> <span class="token number">85</span><span class="token punctuation">,</span> <span class="token number">40</span><span class="token punctuation">,</span> <span class="token number">13</span><span class="token punctuation">,</span> <span class="token number">77</span><span class="token punctuation">,</span> <span class="token number">65</span><span class="token punctuation">,</span> <span class="token number">100</span><span class="token punctuation">]</span>
N <span class="token operator">=</span> <span class="token number">4</span>

<span class="token comment"># Calling the function</span>
LargestFunc<span class="token punctuation">(</span>my_list<span class="token punctuation">,</span> N<span class="token punctuation">)</span>
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Output

Largest numbers = [100, 85, 77, 65]<b>
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Python program to find N largest elements from a list using the sort()

We will use a built-in function sort() to find the N largest elements from a List ?

Example

<div class="execute"></div><div class="code-mirror  language-python" contenteditable="plaintext-only" spellcheck="false" style="outline: none; overflow-wrap: break-word; overflow-y: auto; white-space: pre-wrap;"><span class="token comment"># Create a List</span>
myList <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token number">120</span><span class="token punctuation">,</span> <span class="token number">50</span><span class="token punctuation">,</span> <span class="token number">89</span><span class="token punctuation">,</span> <span class="token number">170</span><span class="token punctuation">,</span> <span class="token number">45</span><span class="token punctuation">,</span> <span class="token number">250</span><span class="token punctuation">,</span> <span class="token number">450</span><span class="token punctuation">,</span> <span class="token number">340</span><span class="token punctuation">]</span>

<span class="token keyword">print</span><span class="token punctuation">(</span><span class="token string">"List = "</span><span class="token punctuation">,</span>myList<span class="token punctuation">)</span>

<span class="token comment"># The value of N</span>
n <span class="token operator">=</span> <span class="token number">4</span>

<span class="token comment"># First, sort the List</span>
myList<span class="token punctuation">.</span>sort<span class="token punctuation">(</span><span class="token punctuation">)</span>

<span class="token comment"># Now, get the largest N integers from the list</span>
<span class="token keyword">print</span><span class="token punctuation">(</span><span class="token string">"Largest integers from the List = "</span><span class="token punctuation">,</span>myList<span class="token punctuation">[</span><span class="token operator">-</span>n<span class="token punctuation">:</span><span class="token punctuation">]</span><span class="token punctuation">)</span>
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Output

List = [120, 50, 89, 170, 45, 250, 450, 340]
Largest integers from the List = [170, 250, 340, 450]