## Question

Asked By – User

Suppose I have and m x n array. I want to pass each column of this array to a function to perform some operation on the entire column. How do I iterate over the columns of the array?

For example, I have a 4 x 3 array like

```
1 99 2
2 14 5
3 12 7
4 43 1
for column in array:
some_function(column)
```

where column would be “1,2,3,4” in the first iteration, “99,14,12,43” in the second, and “2,5,7,1” in the third.

**Now we will see solution for issue: Numpy how to iterate over columns of array? **

## Answer

Just iterate over the transposed of your array:

```
for column in array.T:
some_function(column)
```

This question is answered By – tillsten

**This answer is collected from stackoverflow and reviewed by FixPython community admins, is licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 **