RAMSES zoom sims - pynbody variables

[Rick Sarmento]

Hello all,

I'm just starting to run ramses zoom simulations. When you run a ramses zoom sim, you have an extra variable -- which I believe is sent to the fortran output files. Pynbody 'confirms' this by saying there are more vars in the output than are specified in the .pynbodyrc spec.  Does anyone have experience with zoom sims and RAMSES? Is this extra variable always tacked onto the end of the output? What's it type?? integer, float, double?

I could likely figure this out by sleuthing the code, but I figured someone here knows the answer.

Thanks,

Rick

ASU

[Paweł Biernacki]

Hi Rick.

I think this is more of a RAMSES-question, rather than a pynbody-question. What I believe you mean by an extra variable is the mask for the zoom. If yes, then you choose it in the RAMSES namelist with ivar_refine in REFINE_PARAMS. It is generally just zeros and ones, but the type is the same as of other variables of RAMSES.

I hope that answers your question.

Cheers,

Pawel

[Rick Sarmento]

Hey Pawel,

I think I was trying to be too brief...  Currently, I have a couple extra scalars in my version of RAMSES that I write out to the hydro_ and part_ files. So I've updated ".pynbodyrc" to let pynbody know their location and type:

particle-blocks=x,y,z,vx,vy,vz,mass,iord,level,age,metal,ppf,pzf,r_abundance,tmp

particle-format=f8,f8,f8,f8,f8,f8,f8,i4,i4,f8,f8,f8,f8,f8,f8

hydro-blocks=rho,vx,vy,vz,p,metal,rpgas,pgf,tv,pzf

hydro-format=f8,f8,f8,f8,f8,f8,f8,f8,f8,f8

However, since I now have a zoom sim, I believe I need to add another variable to these lists. As you note, I have 

REFINE_PARAMS

ivar_refine=11

in my params.nml file, but that variable -- number 11 -- is not specified in the .pynbodyrc file ... and I don't know the fortran type for that variable. Here's the warning pynbody generates when I process the outputs from the zoom sim:

... .local/lib/python2.7/site-packages/pynbody/snapshot/ramses.py:281: RuntimeWarning: More hydro variables (11) are in this RAMSES dump than are defined in config.ini (10) nvar_file, nvar), RuntimeWarning)

Thanks!!

Rick

[Paweł Biernacki]

Hi Rick,

Sorry for the late reply. I think you can safely assume that this one variable will have the same type, so f8.

Pawel