initial_he3 is doubly defined

[Mathijs-Vanrespaille]

I'm using the latest stable MESA version 24.08.1, but also noticed this issue persists in version 24.03.1

The namelist object 'initial_he3' is used in both the star_job and controls namelists of the inlist. Bizarely enough, it seems to be the only one of its kind to be doubly defined as e.g. 'initial_he4' is only used in star_job. The one in star_job has the following documentation:

initial mass fraction of he3. Must be smaller than initial_y. (< 0 means use default which is taken as solar scaled such that he4/he3 has the same value as the Sun)
not used when loading a saved model or a zams model.

while the one in controls has no documentation at all. Do these two objects do the same thing? If so, please remove one (preferably the one in controls as the other initial_ are in star_job). If not, please clarify the difference in the documentation and rename one or both to emphasise that difference.

[Debraheem]

Hi @Mathijs-Vanrespaille, thanks for raising this. It appears the 'initial_he3' and other neighboring controls in start_job are only used when set_uniform_initial_composition = .true., which is .false. by default. see https://docs.mesastar.org/en/latest/reference/star_job.html#set-uniform-initial-composition.

In fact i was and still am a little confused by what the difference is between setting set_uniform_initial_composition = .true. or .false. .

I will investigate further, but either way we can add some documentation to clarify this.