[BUG] resolve redundant or problematic statements in numba bounding matrix routines

[albertoazzari]

Reference Issues/PRs

Fixes #6166

What does this implement/fix? Explain your changes.

Remove superfluous if statement

Does your contribution introduce a new dependency? If yes, which one?

No

What should a reviewer concentrate their feedback on?

Did you add any tests for the change?

No

Any other comments?

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[fkiraly]

Thanks!

Btw, not blocking, but if we're already at it.

I'm noticing a lot more weirdness here, namely around upper_line_y_values as well.

That is, at the start, it's defined as the total number of line values, but later it seems to be used as a particular value, or at least used in a contradicting fashion:

• in line 52, we check that upper_line_y_values == lower_line_y_values and otherwise raise, so afterwards this is a guarantee
• now, in line 70 (on main), same as 64 (after current change), we check again. So we never enter else, and the check is redundant. The statement in else also looks really strange. I think this if/else should also get removed, and only the if block executed.

[fkiraly]

Also removed the second one.