Combines a for loop into the creation of a new list based on an existing list.
new_list = [<expression> for <element> in <collection>]
source = [1, 2, 3, 4]
NewList = [item * 2 for item in source]
print(NewList) //Will print: [2, 4, 6, 8]
Adding conditional arguments
if
You simply add an if statement to the end:
new_list = [<expression> for <element> in <collection> if <expression>]
source = [1, 2, 3, 4]
NewList = [item * 2 for item in source if item >= 2]
print(NewList) //Will print: [6, 8]if else
new_list = [<expression> for <element> in <collection> if <expression>]
source = [1, 2, 3, 4]
NewList = [item * 2 if item >= 2 else item * 1 for item in source]
print(NewList) //Will print: [1, 2, 6, 8]Examples
Create list with 100 entries of 0
my_list = [0 for i in range(5)] #Create a list 5 entries long containing 0Create list with 100 random entries
random_list = [random.randint(0, 100) for i in range(5)] #Create a list 5 entries long that has a random number in each from 0 to 100 (inclusive)
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