Deleting elements from a list if they do not follow 'if' 'or' statements

Question

I am trying to get rid of unwanted variables in a list. I need to have two condition: one is if making sure the values in my array are smaller than a variable A, and the other is making sure they are not equal to another variable B.

This code dose not work:

original_Ar = [0,1,2,3,4,5,6,7,8,9,10,11,12]
new_Ar = [s for s in original_Ar if (s != 2) or (s < 10)]

print (new_Ar)

while if I split it into two statements (instead of the or statement) - they do work:

original_Ar = [0,1,2,3,4,5,6,7,8,9,10,11,12]
print ([s for s in original_Ar if (s != 2)])
print ([s for s in original_Ar if (s < 10)])

Any idea how can I do that in one line?

Out of interest why did you use `or`, since you used "and" when you wrote the question? — doctorlove, Feb 01 '17 at 16:05

score 6 · Accepted Answer · answered Feb 01 '17 at 16:03

You have your boolean logic mixed up. You want to include all values that are not equal to 2 and are smaller than 10:

new_Ar = [s for s in original_Ar if s != 2 and s < 10]
#           *both* conditions must be true ^^^

Otherwise, you'd include s = 2, because it is smaller than ten, and you'd include s = 11 and s = 12, because both are not equal to two!

Deleting elements from a list if they do not follow 'if' 'or' statements

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