checking if all elements in a list are equal to a certain value

Question

I'd like to check if all elements within my list are equal to a certain value (that being, '1'). For example:

check_a = False
check_b = False
check_c = False

a = [0, 0, 0, 0, 0]
b = [0, 1, 1, 0, 0]
c = [1, 1, 1, 1, 1]

if all in a == 1:
    check_a = True

elif all in b == 1:
    check_b = True

elif all in c == 1:
    check_c = True

rv.kvetch · Answer 1 · 2022-05-19T13:13:29.673

-3

You are quite close. It looks like you can just use all(elem == 1 for elem in list) in this case:

check_a = check_b = check_c = check_d = False

a = [0, 0, 0, 0, 0]
b = [0, 1, 1, 0, 0]
c = [1, 1, 1, 1, 1]
# notice we want this to result in `False`
#  c = [1, True, 1, 1, 1]
d = [1, 2, 3, 1, 5]


def check_all(L: list):
    return all(x == 1 and x is not True for x in L)


if check_all(a):
    check_a = True

if check_all(b):
    check_b = True

if check_all(c):
    check_c = True

if check_all(d):
    check_d = True


# False False True False
print(check_a, check_b, check_c, check_d)

edited May 19 '22 at 13:13

answered May 19 '22 at 13:04

rv.kvetch

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3

Your function `check_all` is really just `all`. It would be shorter to just do `check_a = all(a)`. This looks over complicated – Mateo Vial May 19 '22 at 13:05
3

This will return `True` even if `a = [2,2,2,2]` without any `1` in it. – leleogere May 19 '22 at 13:06
good point. updated for `x==1` and also check if `x` is a bool type, which is common issue sometmies as well. – rv.kvetch May 19 '22 at 13:08

checking if all elements in a list are equal to a certain value

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