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 COSMOMC: all_l_exact data format Goto page Previous  1, 2
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kumar pandey

Joined: 26 Nov 2008
Posts: 3
Affiliation: Inter University Centre for Astronomy and Astrophysics

 Posted: November 27 2008 Hi can you please have a look : http://cosmocoffee.info/viewtopic.php?t=1276 thanks, R.
Paniez Paykari

Joined: 08 Jun 2007
Posts: 14
Affiliation: CEA

 Posted: December 15 2010 Hi All, Does the $C_\ell$s in the planck.dat file have to be necessarily smooth? Or can we have a simulated $C_\ell$ from a CMB map? I appreciate the help. Thanks Paniez
Antony Lewis

Joined: 23 Sep 2004
Posts: 675
Affiliation: University of Sussex

 Posted: December 15 2010 You can use a simulation, just don't expect the posteriors to peak at exactly the simulation input values.
Paniez Paykari

Joined: 08 Jun 2007
Posts: 14
Affiliation: CEA

 Posted: December 15 2010 Thank you. So, that means I should expect some bias? I can trust the errors though? Paniez
Alex Conley

Joined: 08 Feb 2005
Posts: 11

 Posted: April 23 2011 I'm a bit confused – why, in the example code, does one write CTT+Nl and CEE+noiseFac*Nl, but does not include any noise term when writing out CTE?
Antony Lewis

Joined: 23 Sep 2004
Posts: 675
Affiliation: University of Sussex

 Posted: April 23 2011 Just assuming the simple case where there is no noise correlation between Q/U and T.
Alessio Notari

Joined: 26 Nov 2005
Posts: 7
Affiliation: McGill U.

 Posted: July 11 2011 Hello, I am trying to use the all_l_exact format on CosmoMC with the above procedure with some C_l table produced by the Healpix package anafast, and it works well :) . One simple question: does it work only for full-sky data or should I do something more complicated (such as using planck_like.f90) when I put a mask with anafast on my sky maps? And by the way, what is the planck_like.f90 routine doing exactly and how do I use it? (I cannot find any instructions on the web) ... thanks a lot for your help! Alessio
Antony Lewis

Joined: 23 Sep 2004
Posts: 675
Affiliation: University of Sussex

 Posted: July 12 2011 Planck_like implements the approximation of 0801.0554 as well as simple schemes like full-sky and Gaussian. You probably should use something that accounts for the covariance when using cut-sky data. For sample data files see the bottom of http://cosmologist.info/weightmixer/ or the python exact simulation script supplied with most recent cosmomc.
Alessio Notari

Joined: 26 Nov 2005
Posts: 7
Affiliation: McGill U.

 Posted: July 12 2011 Thanks for the answer. Though, I am not sure if I understand the way to preceed. How do I tell to cosmomc that there is nontrivial covariance due to cut-sky? Moreover, in the all_lexact format why is there an fsky column if this is valid only for full sky? cheers
Alessio Notari

Joined: 26 Nov 2005
Posts: 7
Affiliation: McGill U.

 Posted: July 14 2011 I guess I should probably use the .newdat format for the data, which is related to this: http://cosmocoffee.info/viewtopic.php?p=4068 and to this: http://www.astro.caltech.edu/~tjp/CBI/data2006/index.html Could anyone clarify if this is the right way to proceed and how this format can be used for mock data? (there are no answers to the questions in the above link) thanks again
Jason Dossett

Joined: 19 Mar 2010
Posts: 21
Affiliation: The University of Texas at Dallas

Posted: February 28 2012

 Antony Lewis wrote: Planck_like implements the approximation of 0801.0554 as well as simple schemes like full-sky and Gaussian. You probably should use something that accounts for the covariance when using cut-sky data. For sample data files see the bottom of http://cosmologist.info/weightmixer/ or the python exact simulation script supplied with most recent cosmomc.

Hi,
I am trying to use the makePerfectForcast.py python script to create a new dataset for some future simulated data. I understand how to produce the input files:
lensedTotClFileRoot and lensPotential.
I am however unsure how exactly to construct the reconNoise input file. Any help would be greatly appreciated.

Thanks,
Jason
Antony Lewis

Joined: 23 Sep 2004
Posts: 675
Affiliation: University of Sussex

 Posted: February 28 2012 You only need reconNoise if you want to include CMB lensing reconstruction (in which case it is the reconstruction noise variance, which you can calculate for isotropic full sky case using standard result involving 3j sum).
Jason Dossett

Joined: 19 Mar 2010
Posts: 21
Affiliation: The University of Texas at Dallas

 Posted: March 03 2012 Thanks Antony.
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