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Is there a function to give the number of elements in a list that passes a crite...

 3 years ago
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Is there a function to give the number of elements in a list that passes a criterion?

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So i have an array, say something like [5,2,2,0], is there a function to return the number of elements that pass a criterion?

Currently i'm doing this:

a = [5,2,2,0]
len([i for i in a if i > 0])

someone suggested this approach too:

sum(b > 0 for b in a)

but IMO this is really the same thing, just a little less readable.

Is there some method like this i could use:

def crit(x): return x > 0
a.count(criterion=crit)

You can use filter function len(filter(crit, a))

Tags python

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