IS it Erro in gini()?

[craftsliu]

Describe the bug

To Reproduce
import numpy as np

y = np.array([3, 1, 4, 1, 5])
p = np.array([2.5, 0.8, 4.2, 1.2, 4.9])

arr = np.array([y, p]).transpose()
print(arr)

true_order = arr[arr[:, 0].argsort()][::-1, 0]

按照预测值从大到小排序

pred_order = arr[arr[:, 1].argsort()][::-1, 0]

打印排序结果

print("按真实值排序：", true_order)
print("按预测值排序：", pred_order)
then it print :
[[3. 2.5]
[1. 0.8]
[4. 4.2]
[1. 1.2]
[5. 4.9]]
按真实值排序： [5. 4. 3. 1. 1.]
按预测值排序： [5. 4. 3. 1. 1.]
Expected behavior
if change

按照预测值从大到小排序

pred_order = arr[arr[:, 1].argsort()][::-1, 1]

then it will print
[[3. 2.5]
[1. 0.8]
[4. 4.2]
[1. 1.2]
[5. 4.9]]
按真实值排序： [5. 4. 3. 1. 1.]
按预测值排序： [4.9 4.2 2.5 1.2 0.8]

[jeongyoonlee]

@ppstacy, @paullo0106, @zhenyuz0500, @vincewu51, Can you take a look at this issue?