### CosmoMC: SDSS data

Posted:

**February 21 2006**Hi All,

There are two parameters for the SDSS data in the CosmoMC code: mpk_points and mpk_kbands.

The comment on mpk.f90 says:

max_mpk_points_use ! in case you don't want the smallest scale modes (eg. sdss)

min_mpk_points_use ! in case you don't want the largest scale modes

max_mpk_kbands_use ! in case you don't want to calc P(k) on the smallest scales (will truncate P(k) to zero here!)

min_mpk_kbands_use ! in case you don't want to calc P(k) on the smallest scales (will truncate P(k) to zero here!)

So I guess mpk_points represents different data set; large value of max_mpk_points means small scales data and small value of min_mpk_points means large scales data. As for the mpk_kbands, it just means the range of k/h space at which we calculate the spectrum. Am I right?

Besides, both max_mpk_kbands and min_mpk_kbands say "smallest scales", a typo?

(I am using July 2005 version.)

Thanks.

Loison Hoi

21 Feb 2006

There are two parameters for the SDSS data in the CosmoMC code: mpk_points and mpk_kbands.

The comment on mpk.f90 says:

max_mpk_points_use ! in case you don't want the smallest scale modes (eg. sdss)

min_mpk_points_use ! in case you don't want the largest scale modes

max_mpk_kbands_use ! in case you don't want to calc P(k) on the smallest scales (will truncate P(k) to zero here!)

min_mpk_kbands_use ! in case you don't want to calc P(k) on the smallest scales (will truncate P(k) to zero here!)

So I guess mpk_points represents different data set; large value of max_mpk_points means small scales data and small value of min_mpk_points means large scales data. As for the mpk_kbands, it just means the range of k/h space at which we calculate the spectrum. Am I right?

Besides, both max_mpk_kbands and min_mpk_kbands say "smallest scales", a typo?

(I am using July 2005 version.)

Thanks.

Loison Hoi

21 Feb 2006