CosmoMC: A problem when adding a new parameter

Use of Cobaya. camb, CLASS, cosmomc, compilers, etc.
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Bo Feng
Posts: 11
Joined: January 07 2005
Affiliation: Research Center for the Early Universe, University of Tokyo

CosmoMC: A problem when adding a new parameter

Post by Bo Feng » February 15 2006

On behalf of my friend Lele, I hope someone would reply to me on the following question, thanks in advance!


I'm using cosmomc, and would like to use a new parameter (new) as an input
parameter.This new parameter is added to the subroutine Initrecfast(xxxx,new)
in recfast.f90 . I've added CMB%new = Params( in the params_CMB.f90 file
and modified setting.f90 to make hard num =8 (7+1).I also add the limits
in my params.ini file accordingly. And set

propose_matrix =
estimate_propose_matrix = T

If I run CAMB , it's ok. But when run cosmomc, the code always stop and say:
Finding max-like point
reading WMAP data
WMAP read
ERROR: Trial parameters excluded by prior or error in likelihood'
'Try starting further away from problem regions?'

What am I doing wrong?

Antony Lewis
Posts: 1936
Joined: September 23 2004
Affiliation: University of Sussex
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Re: CosmoMC: A problem when adding a new parameter

Post by Antony Lewis » February 15 2006

It usually means you've set the range or start point wrong in params.ini, or that your likelihood is returning a bad value.

Try without using estimate_propose_matrix. Also make sure you run make clean after editing settings.f90 etc.

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