Cosmomc: Queries

[ajey 0]

have recently started using COSMOMC for carrying out parameter estimation and found it extremely useful and versatile. However, there are few things I am unable to understand and am facing some problems. Kindly give me some suggestions.1) I would like to do a COSMOMC run with only the WMAP TT data excluding the TE data which as I understand means putting "num_cls" equal to 1. Accordingly I changed the value of "num_cls" (wherever it exists) but it gives an error "MCMC could not start after 1000 tries....." What is going wrong? Am I missing something!2) I would also like to run COSMOMC but with a scale invariant power spectrum fixing the spectral index, ns (=1). I tried fixing the value in power_tilt.f90 as well as fixing ns parameter values to 1 in 'params.ini' but none of them worked.3) I would like to change the CAMB part to use my own set of inflationary parameters so as I understand I have to replace the power_tilt.f90 routine with my own routine (primarily the scalar and tensor power parts of it). Which are the other files which need modifications. Also I would like to know where in the CAMB part do you fix (or you vary) the value of scalar to tensor power amplitude. I have read the FAQs and readme sections as well.Kindly give inputs/suggestions. Thanks.

[cumar11 0]

have recently started using COSMOMC for carrying out parameter estimation and found it extremely useful and versatile. However, there are few things I am unable to understand and am facing some problems. Kindly give me some suggestions.

 

1) I would like to do a COSMOMC run with only the WMAP TT data excluding the TE data which as I understand means putting "num_cls" equal to 1. Accordingly I changed the value of "num_cls" (wherever it exists) but it gives an error "MCMC could not start after 1000 tries....." What is going wrong? Am I missing something!

 

2) I would also like to run COSMOMC but with a scale invariant power spectrum fixing the spectral index, ns (=1). I tried fixing the value in power_tilt.f90 as well as fixing ns parameter values to 1 in 'params.ini' but none of them worked.

 

3) I would like to change the CAMB part to use my own set of inflationary parameters so as I understand I have to replace the power_tilt.f90 routine with my own routine (primarily the scalar and tensor power parts of it). Which are the other files which need modifications. Also I would like to know where in the CAMB part do you fix (or you vary) the value of scalar to tensor power amplitude. I have read the FAQs and readme sections as well.

 

Kindly give inputs/suggestions. Thanks.

178348[/snapback]

I have knoew idea what you are talking about,

 

what is COSMOMC

[ajey 0]

this program is four this: if you get the idea!

 

it is fourstar observacion end math planning of star moval