After I compiled CosmoMC, it could retrun the best-fit values of the 6-parameter model. However, when I modified the file "params.ini" to use "w" as a parameter, an error occurred. The only change to the original file is
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action = 2
#parameter start center, min, max, start width, st. dev. estimate
#w
param7 = -1 -1.5 -0.5 0.01 0.01
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This error occurred when running "./cosmomc params.ini":
...
ERROR: Trial parameters hit prior or error in function evaluation
Try starting further away from problem regions?
I changed the "param7" as
param7 = -1 -1.1 -0.9 0.01 0.01
or
param7 = -1 -1.5 -0.5 0.1 0.1
then this error also occurred. If I changed the parameter "omk" instead of "w" as
#omk
param5 = 0 -0.1 0.1 0.01 0.01
this error would also occur.
Why this error? How to use "w" as a parameter? Thank you very much!