Question

Can I specify other arguments in map ?

For example, I have the following code:

def f(a, b):
    return a + b
l = [1, 2, 3]
ll = map(f, l)

How can I give an argument to the map above so that each element of ll is the sum of one element in l and the given argument?

For example, if I can use something like map(f(2,), l), I will get [3, 4, 5] as result.

I know I can achieve the same result by list comprehension, or a for loop, but I just want to know if it is possible to do it in a map way.

Answer 1

map itself does not directly provide a way to do that. However, you can do it by using functools.partial to pre-specify the static argument:

>>> def add(x, y):
...     return x+y
>>> map(functools.partial(add, y=10), [1, 2, 3])
[11, 12, 13]

However, as @jamylak suggested in a comment, there’s little reason to do this. If you don’t want to store the result, just do a regular for loop:

for item in [1, 2, 3]:
   add(item, 10)