Numpy delete submatrix-CodePudding

I have a numpy array of float. I was wondering if there are any methods or functions to cut/delete a part of matrix.

matrix = np.arange(400).reshape(20,20)

I considered extracting by indexing the rows/columns by slicing (Cut(matrix[row_idx,:][:,col_idx])) or using functions np.ix, but that gives me a submatrix, and I need an old matrix without a select part.

The picture below shows what I mean. I want to get a matrix without the column and rows marked in yellow.

Is there any way to do this? Thank you for your any help.

CodePudding user response：

You can use np.delete() to delete the columns/rows that you want. This will return a new array

https://numpy.org/doc/stable/reference/generated/numpy.delete.html

CodePudding user response：

If you want to build a new matrix, you could use concatenate:

newmatrix = np.concatenate(
    (np.concatenate((matrix[:8,:8], matrix[13:, :8])),
     np.concatenate((matrix[:8,13:], matrix[13:, 13:]))),
    axis=1)