BLD: interpolate: _interpnd_info does not need installing

[ev-br]

There is no need to install _interpnd_info.py: this is a helper file, it does not provide any user-facing functionality, it is not accessible from the scipy.interpolate namespace --- it can live in the repo but there is hardly any reason for it to end up on a user system.

[ev-br]

I wanted to write "it's similar to scipy/special/_precompute which does not get installed" --- but _precompute does get installed, cf https://github.com/scipy/scipy/blob/main/scipy/special/meson.build#L408 --- ! I actually wonder if it needs to @steppi?

[steppi]

I wanted to write "it's similar to scipy/interpolate/_precompute which does not get installed" --- but _precompute does get installed, cf https://github.com/scipy/scipy/blob/main/scipy/special/meson.build#L408 --- ! I actually wonder if it needs to @steppi?

Some of the stuff is imported in test code,

https://github.com/scipy/scipy/blob/main/scipy/special/tests/test_precompute_expn_asy.py
https://github.com/scipy/scipy/blob/main/scipy/special/tests/test_precompute_gammainc.py
https://github.com/scipy/scipy/blob/main/scipy/special/tests/test_precompute_utils.py

but it looks like this is for tests that the _precompute scripts are working correctly, not for direct tests of anything user facing.

[tylerjereddy]

Seems safe enough, there's a sympy import in there too, so clearly not something to be exported to users, and CI is happy.

Thanks Evgeni