Re: Vectorization and Numeric (Newbie)

"map" takes a function and a list, applies the function to each item in
a list, and returns the result list. For example:

def f(x): return x + 4

numbers = [4, 8, 15, 16, 23, 42]
map(f, numbers)
[8, 12, 19, 20, 27, 46]

So, rather that ask if there is a different way to write f, I'd just
use f in a different way.

Another way to accomplish the same result is with a list comprehension:

[f(x) for x in numbers]
[8, 12, 19, 20, 27, 46]

As you can see, if you wanted to "calculate all the values from 1 to
n," you could also use these techniques instead of a loop.

n = 10
[f(x) for x in xrange(1, n+1)]
[5, 6, 7, 8, 9, 10, 11, 12, 13, 14]

.

Relevant Pages

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