Try to duplicate less code

[hofnerb]

@ja-thomas, we should try to use better functional units to avoid duplication of code. Currently, we have a lot of spaghetti code instead of proper functional programming.

Can we aim for that in the next release, i.e. after the initial release of the non-cyclic fitting?

[hofnerb]

Perhaps we can furthermore already use object orientation within the fitting algorithm

[ja-thomas]

Should be better now. The code could be made nicer in the future, but that would require major refactoring (maybe even some on mboost). I don't think I have the time for that currently, but we can keep the issue open if you want to.