Replaced concat_horizontal with concat

[pvprajwal]

Fixes #1330

Replaced concat_horizontal with concat. The axis parameter can be used to specify whether to concatenate horizontally or vertically.
axis=1 or axis='columns' can be used for horizontal
axis=0 or axis='index' can be used for horizontal

[Vincent-Maladiere]

Hello @pvprajwal, thank you for this PR! Here are a couple of remarks

[jeromedockes]

Thanks a lot for working on this @pvprajwal and welcome to skrub 🎉 ! this is great, you took on a challenging issue for your first contribution and the result is looking good! I agree with @Vincent-Maladiere 's point that we should not support axis='index' or axis='columns' because 'index' only makes sense for pandas. it's looking good otherwise :) 🚀

[pvprajwal]

Thanks so much @jeromedockes ! I am glad to be part of the skrub community. I appreciate the feedback from you and @Vincent-Maladiere .

Regarding axis='horizontal'/'vertical', do we want to support that?

[Vincent-Maladiere]

It's our pleasure @pvprajwal, thank you for contributing! If we don't support axis='index'/'column', then I guess we shouldn't support axis='horizontal'/'vertical' either, WDYT?

[jeromedockes]

let's go with just axis=0 or axis=1 for now, it's easier to add stuff later than to remove it

[pvprajwal]

Alright, I'll update the code.

[jeromedockes]

Thank you very much @pvprajwal !! super useful

[Vincent-Maladiere]

Looks good! Thanks @pvprajwal :)

[Vincent-Maladiere]

Merging after the conflict have been sorted out

[pvprajwal]

conflicts resolved @Vincent-Maladiere .

[GaelVaroquaux]

Thanks a lot, @pvprajwal ! Much appreciated!