[TEP007] Isotope uniform config option

[vg3095]

This PR is for adding support to read uniform isotope abundances.
For seeing sample output :
Notebook (Updated)
Config (Updated)

For Isotopes , you will need to mention mass-no. in every case.
For example Ni will not work , Ni56 , Ni58 will work.

It is because ,I think Tardis does not store mass_no. of stable isotope elements, so as of now , it supports this type of format( ElementMass_no)

[yeganer]

I think in the config we should merge abundances and isotope abundances.
So specifying Ni: 0.2 and Ni56: 0.1 should result in Ni: 0.3 at t=0.
The same goes for the abundance file.

[wkerzendorf]

@vg3095 : the suggestion by @yeganer is what we want to implement.

[vg3095]

@wkerzendorf Please review .

[wkerzendorf]

maybe this splitting - might be better performed earlier in the process and not in the init of the model (generally keeping logic out of inits is good practice).

[wkerzendorf]

what happens when this fails as well. Actually you can probably use pyne for both. try that.

[vg3095]

@wkerzendorf If this fails, then it will throw error raised by pyne.
(Ex- RuntimeError: Not a Nuclide! NIEFEG --> 0, where Niefeg is some wrong element defined in config)

If I use pyne then I can replace this by something like this:

try:
      find atomic_no and mass_no by pyne
      if mass_no!=0:
           Its a isotope
      else:
           Its a normal element
except RuntimeError as e:
      raise RuntimeError('Abundances are not defined properly in config', e.args)

Pyne returns mass_no zero whenever we pass elements in normal form(without mass_no attached), something like this:

>>> nucname.anum('O')
0
>>> nucname.anum('Ni')
0

[wkerzendorf]

@vg3095 try to figure out how to pass elements to pine - I'm sure that works.

[wkerzendorf]

@vg3095 I think that looks good - apart from the points I made - good job!!

[wkerzendorf]

@vg3095 looks good @tardis-sn/tardis-core can someone cross check before I merge?