Learn Web Development with Python

Filtering a comprehension

We can apply filtering to a comprehension. Let's do it first with filter. Let's find all Pythagorean triples whose short sides are numbers smaller than 10. We obviously don't want to test a combination twice, and therefore we'll use a trick similar to the one we saw in the previous example:

# pythagorean.triple.pyfrom math import sqrt# this will generate all possible pairsmx = 10triples = [(a, b, sqrt(a**2 + b**2))    for a in range(1, mx) for b in range(a, mx)]# this will filter out all non pythagorean triplestriples = list(    filter(lambda triple: triple[2].is_integer(), triples))print(triples)  # prints: [(3, 4, 5.0), (6, 8, 10.0)]

A Pythagorean triple is a triple (a, b, c) of integer numbers satisfying the equation ...