Simplifying argmin and argmax where possible

[tdegeus]

Hopefully this avoids mysterious segmentation faults on Windows

Checklist

• The title and commit message(s) are descriptive.
• Small commits made to fix your PR have been squashed to avoid history pollution.
• Tests have been added for new features or bug fixes.
• API of new functions and classes are documented.

Description

[JohanMabille]

Thanks!