Please note, this is a STATIC archive of website www.w3resource.com from 19 Jul 2022, cach3.com does not collect or store any user information, there is no "phishing" involved.
w3resource

Python: Get every nth element in a given list

Python List: Exercise - 269 with Solution

Write a Python program to get the every nth element in a given list.

Use slice notation to create a new list that contains every nth element of the given list

Sample Solution:

Python Code:

def every_nth(nums, nth):
  return nums[nth - 1::nth]
print(every_nth([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 1))
print(every_nth([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 2))
print(every_nth([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 5))
print(every_nth([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 6))

Sample Output: 

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
[2, 4, 6, 8, 10]
[5, 10]
[6]

Flowchart:

Flowchart: Get every nth element in a given list.

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:


Python Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a Python program to get a list with n elements removed from the left, right.
Next: Write a Python program to check if the elements of the first list are contained in the second one regardless of order.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Python: Tips of the Day

Find current directory and file's directory:

To get the full path to the directory a Python file is contained in, write this in that file:

import os 
dir_path = os.path.dirname(os.path.realpath(__file__))

(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)

To get the current working directory use

import os
cwd = os.getcwd()

Documentation references for the modules, constants and functions used above:

  • The os and os.path modules.
  • The __file__ constant
  • os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")
  • os.path.dirname(path) (returns "the directory name of pathname path")
  • os.getcwd() (returns "a string representing the current working directory")
  • os.chdir(path) ("change the current working directory to path")

Ref: https://bit.ly/3fy0R6m