如何按列的降序对二维数组进行排序？

array([[ 0.  ,  0.04],
       [ 0.  ,  0.1 ],
       [ 0.  ,  0.2 ],
       [ 0.  ,  0.4 ],
       [ 0.27,  1.  ],
       [ 0.3 ,  1.  ]])

How to sort the array by the second column in descend order in an simple way ? The result's shape is also (6,2).

如何以简单的方式按降序排列第二列的数组?结果的形状也是(6,2)。

1 个解决方案

#1

Get argsort indices for the second column, flip them and index into rows -

获取第二列的argsort索引,翻转它们并将其索引到行中 -

a[a[:,1].argsort()[::-1]]

Alternatively, get argsort indices on negated version and index into rows -

或者,获取否定版本的argsort索引并将索引转换为行 -

a[(-a[:,1]).argsort()]