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Python Functional Python Functional Workhorses Map Comprehension

Andrew Winkler
Andrew Winkler
37,739 Points
Posted by Andrew Winkler
Andrew Winkler
37,739 Points

What am I doing wrong here? reduce vs list comprehension?

I've re-watched the video, looked through the docs, and am now resorting to trial-and-error. Can someone please go ahead and explain this to me? I still don't fully understand what a list comprehension entails as well.

maps.py 
dimensions = [
    (5, 5),
    (10, 10),
    (2.2, 2.3),
    (100, 100),
    (8, 70),
]

def area(tup):
   return tup[0] * tup[1] 

areas = reduce(add, map(area, dimensions))

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

First some hints: You won't need reduce. And a list comprehension is a list, so it will be enclosed in []'s, and will have a kind of a modified loop syntax inside. In fact, you could get the same result using a loop. And remember to use your area function.

Got it now? If not, you might try reviewing the video.

If that still doesn't help, and you'd like to peek at an answer...

:warning: Spoiler Alert

areas = [ area(item) for item in dimensions ]
Andrew Winkler
Andrew Winkler
37,739 Points
Andrew Winkler
Andrew Winkler
37,739 Points

Thank you. This was so easy, I just didn't see it. I was anticipating something more advanced.