在python中的函数上应用过滤器

Question

I am getting an unexpected output when I execute the following python code. Iam new at python.

def foo(n):
    return n+2;
print (filter(foo,[1,2]))

i was expecting output as :-

[3,4]

but Iam getting output as:-

[1,2] 

please help me solve this.

Answer 1

What you described is map and not filter .

def foo(n):
    return n+2;
print (map(foo,[1,2]))

Prints out

[3,4]