shripati007 - 5 months ago 30

Python Question

I have 2 multidimensional arrays , both of size 128X640X5. 5 is the number of channels for the matrices. I wish to add the respective channel values of both the matrices for every point in the matrices. For eg if we have A and B as 2 matrices, I wish to do an operation something like this:

A(x,y,0)+B(x,y,0) =A(x,y,0). This should add the 0th channel values of points x and y in both A and B and then store it back in A. Similiary I wish to do it for other 4 channels also. Any idea on how to do this in python? I am using numpy array of python and basically working on image manipulation problem.

Answer

In order to add each corresponding point of a `ndarray`

in numpy you can use numpy's add function (numpy.add).

It will add up each corresponding point of two ndarrays which have the **same** shape. If the arrays do not have the same shape, it will `broadcast`

(change their shape) so that they can be added together.

In your case, you would simply write:

```
import numpy as np
C = np.add(A, B)
```

**Source:**

http://docs.scipy.org/doc/numpy/reference/generated/numpy.add.html