Python program to create a list centered on zero

Given two integer variables, limit and diff, write a Python program to create a list that is centered on zero, using limit, which specifies limit of the list and diff that specifies the common difference between integers.

Examples:

Input : limit = 1, diff = 0.5
Output : [-1, -0.5, 0.0, 0.5, 1]

Input : limit = 25, diff = 5
Output : [-25, -20, -15, -10, -5, 0, 5, 10, 15, 20, 25]

 



Approach #1 : Naive Approach

This is a naive approach to the above problem. First, create an empty list ‘lst’, and then we use a while loop to append the next integer with a difference equal to ‘diff’.

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program to Convert a 
# list to dictionary
  
def create(limit, diff):
          
    lst = [-limit]
    while lst[-1] < limit:
        lst.append(lst[-1] + diff)
    lst[-1] = limit
    return lst
          
# Driver code
limit = 1
diff = 0.5
print(create(limit, diff))

chevron_right


Output:

[-1, -0.5, 0.0, 0.5, 1]

 
Approach #2 : Using Python Numpy

Using Numpy module makes the solution a lot easier. In this method, we use np.arange which return evenly spaced values within a given interval ‘diff’.

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program to Convert a 
# list to dictionary
import numpy as np
  
def create(limit, diff):
    lst = np.arange(diff, limit, diff)
    if (lst[-1] != limit):
        lst = np.r_[lst, limit]
          
    return np.r_[-lst[::-1], 0, lst].tolist()
          
# Driver code
limit = 1
diff = 0.5
print(create(limit, diff))

chevron_right


Output:

[-1, -0.5, 0.0, 0.5, 1]


My Personal Notes arrow_drop_up


If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.




Article Tags :

Be the First to upvote.


Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.