How to add 2 columns in numpy ndarray? [duplicate]

问题

This question already has an answer here:

How to combine two columsn/rows of a matrix in numpy by summing values? (1 answer)

Closed 10 months ago.

I have an numpy ndarray like below:

[[1 9 1 1]
 [9 3 1 1]
 [1 9 9 1]
 [8 2 4 7]]

I want to add last 2 columns values to get below result

[[1 9 2]
 [9 3 2]
 [1 9 10]
 [8 2 11]]

回答1:

Sum, then drop the last column

myArray[:, -2] = myArray[:,-2] + myArray[:,-1] 
myArray = myArray[:,:-1]

来源：https://stackoverflow.com/questions/61092371/how-to-add-2-columns-in-numpy-ndarray