Issue
I’m looking to slice out the minimum value along the first axis of an array.
For example, in the code below, I want to print out np.array([13, 0, 12, 3]).
However, the slicing isn’t behaving as I would think it does.
(I do need the argmin array later and don’t want to just use np.min(g, axis=1))
import numpy as np
g = np.array([[13, 23, 14], [12, 23, 0], [39, 12, 92], [19, 4, 3]])
min_ = np.argmin(g, axis=1)
print(g[:, min_])
What is happening here?
Why is my result from the code
[[13 14 23 14]
[12 0 23 0]
[39 92 12 92]
[19 3 4 3]]
Other details:
Python 3.10.2
Numpy 1.22.1
Solution
If you want use np.argmin, you can try this:
For more explanation : from min_ you have array([0, 2, 1, 2]) but for accessing to array you need ((0, 1, 2, 3), (0, 2, 1, 2)) for this reason you can use range.
min_ = np.argmin(g, axis=1)
g[range(len(min_)), min_] # like as np.min(g ,axis=1)
Output:
array([13, 0, 12, 3])
Answered By – I'mahdi
Answer Checked By – Katrina (BugsFixing Volunteer)