Use unit.name as key cache

[EdgarGF93]

For two units called scattering_angle_horz and scattering_angle_vert ; the key to cache the arrays is the same for both units (scattering).
Can we change it and use just the full unit.name?

[kif]

If I understand correctly, the issue comes from the _ in your unit name.
If we agree that the second half should never gave a _ as separator, wouldn't it be simpler to use:
space = "_".join(name.split("_")[:-1]))
instead of
space = name.split("_")[0]
This would avoid different behaviour for azimuthal- and fiber- units ?

[EdgarGF93]

why we cannot use the whole unit.name as cache key?
-> Because units with same equation and different scale should share the cache arrays
Then yes, for the moment we can use every part of the name separated by "_" except the last part, which is mandatory to be the units (deg, m, mm...)
In the future, we should use a more explicit approach, like an attribute "cache_key" or "unit" for the methods register_..._unit

[EdgarGF93]

something like this?

[kif]

LGTM