> import torch
> a=torch.randn((3,5))
> a
tensor([[-0.4790, -0.6308, 0.2370, 0.0380, -0.0579],
  [-0.6712, -3.5483, -0.2370, -0.8658, 0.4145],
  [-1.4126, -0.8786, -0.4216, -0.0878, -1.4015]])
> _,pre=a.topk(1,dim=1,largest=True)
> pre
tensor([[2],
  [4],
  [3]])
> _
tensor([[ 0.2370],
  [ 0.4145],
  [-0.0878]])
> _,pre=a.topk(1,dim=1,largest=False)
> pre
tensor([[1],
  [1],
  [0]])
> _
tensor([[-0.6308],
  [-3.5483],
  [-1.4126]])

import numpy as np
a = np.array([1,4,3,5,2])
b = np.argsort(a)
print(b)