Python - numpy 矩阵每列中前 n 个元素的索引

Question

What is the best way to select top n elements from each column of a numpy matrix of 2 dimension?(apart from using for loop)

Answer 1

Maybe slicing?

if you have:

matr = np.random.randn(4, 5)

you can simply select for example first 2 elements of first 2 cols doing:

matr[:2,0:2]

Try those snippets of code and check if it's what you was looking for.