Python numpy - 用升序填充 numpy 数组

Question

I am trying to initialize a numpy array or a list with ascending values. The number of values is n .

eg: If n = 10

[0,2,4,6,8,10,12,14,16,18]

If n = 2

[0,2]

I am aware that I could use a for like this:

result = []
for x in range(n):
   result.append(x*2)

But when n gets larger this would take a while so I was looking for a faster way.

Answer 1

There is numpy.arange which supports a step parameter:

result = np.arange(0, 2*n, 2)

Answer 2

Alternatively, for a list you can use range 's step parameter:

result = list(range(0, 2*n, 2))