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Often you may be interested in replacing one or more values in a list in Python.
Fortunately this is easy to do in Python and this tutorial explains several different examples of doing so.
Example 1: Replace a Single Value in a List
The following syntax shows how to replace a single value in a list in Python:
#create list of 4 items x = ['a', 'b', 'c', 'd'] #replace first item in list x[0] = 'z' #view updated list x ['z', 'b', 'c', 'd']
Example 2: Replace Multiple Values in a List
The following syntax shows how to replace multiple values in a list in Python:
#create list of 4 items x = ['a', 'b', 'c', 'd'] #replace first three items in list x[0:3] = ['x', 'y', 'z'] #view updated list x ['x', 'y', 'z', 'd']
Example 3: Replace Specific Values in a List
The following syntax shows how to replace specific values in a list in Python:
#create list of 6 items
y = [1, 1, 1, 2, 3, 7]
#replace 1's with 0's
y = [0 if x==1 else x for x in y]
#view updated list
y
[0, 0, 0, 2, 3, 7]
You can also use the following syntax to replace values that are greater than a certain threshold:
#create list of 6 items
y = [1, 1, 1, 2, 3, 7]
#replace all values above 1 with a '0'
y = [0 if x>1 else x for x in y]
#view updated list
y
[1, 1, 1, 0, 0, 0]
Similarly you could replace values that are less than or equal to some threshold:
#create list of 6 items
y = [1, 1, 1, 2, 3, 7]
#replace all values less than or equal to 2 a '0'
y = [0 if x#view updated list
y
[0, 0, 0, 0, 3, 7]
Find more Python tutorials here.