Seg fault in May version of cosmomc

Use of Cobaya. camb, CLASS, cosmomc, compilers, etc.
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Alex Conley
Posts: 11
Joined: February 08 2005

Seg fault in May version of cosmomc

Post by Alex Conley » May 14 2008

The May release of Cosmomc (Union SN sample, etc.) seg faults for me
out of the box (i.e., running ./cosmomc params.ini with the supplied versions
does not work).

The issue seems to be one of variable initialization. The seg fault
is when it tries to write chain results in WriteParams (in params_CMB.f90),
as nuisance_params_used has a very large random value.

Tracing this through the code, I note that
ReadDataSet in cmbdata.F90 does -not- initialize aset%nuisance_parameters
for the WMAP case. Adding a line doing so (i.e.,
aset%nuisance_parameters=0
inside the IF (aname == 'WMAP' ...
statement) seems to fix things, although I'm a little leery
of this solution since I don't understand exactly how the code
is trying to handle the WMAP data.

Antony Lewis
Posts: 1941
Joined: September 23 2004
Affiliation: University of Sussex
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Re: Seg fault in May version of cosmomc

Post by Antony Lewis » May 14 2008

Thanks, yes it should have
aset%nuisance_parameters=0
at the start of the subroutine.

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