This patch implements code described in arXiv:1012.5299 and published in JCAP, with DOI 10.1088/1475-7516/2011/05/016. The patch applies to the January 2010 release of CosmoMC and is unlikely to work with more recent versions of CosmoMC. A more sophisticated interpolation algorithm is described in arXiv:1506.01079.
InterpMC is a patch for CosmoMC which speeds parameter estimation by caching the likelihoods computed as CosmoMC runs, fitting an interpolating polynomial and, when feasible, using the interpolated values in place of a full likelihood computation.
To install InterpMC, download the unix patch file below, and a fresh copy of CosmoMC, then execute the following commands from the shell, in the CosmoMC source directory:
> patch –dry-run -p1 -i interp_mc.patch
[Checks patch will be applied without generating errors]
> patch -p1 -i interp_mc.patch
Then run “make” as usual. Next, edit the params.ini file you are running with to include the following additional lines (possibly with other numerical values of your choice):
do_interp = T
interp_order = 4
factor = 3
cut = 8
faction_cut = 0.2
Now you can run CosmoMC as usual.