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help to use ppf module

Posted: October 24 2014
by Ruth Lazkoz
Hi,

I am trying to interpret the various pieces of help available on this forum and the whole web.

Please, allow me to make (a few) questions that will sound silly to you.

If I get the idea correctly, in order to use the ppf module I should prepare initially a wa.dat file containing something like this (is the sintax correct?):

0. w0 + 1.*wa
0.1 w0 + 0.9*wa
0.2 w0 + 0.8*wa
0.3 w0 + 0.7*wa
0.4 w0 + 0.6*wa
0.5 w0 + 0.5*wa
0.6 w0 + 0.4*wa
0.7 w0 + 0.3*wa

Thanks so much,

Ruth[/list]

help to use ppf module

Posted: October 28 2014
by Erick Almaraz
Dear Ruth.

The use of the wa.dat is optional. If you want to use it, you must give a .dat file containing the values of the factor scale and the equation of state for each a, ie, (a,w(a)).

Regards

Re: help to use ppf module

Posted: October 28 2014
by Ruth Lazkoz
Dear Erick,

do you mean there another way to use the ppf module for one's favourite dark energy parametrization? I mean, another way rather than specifying it through an wa.dat file (or any other name)?

Best,

Ruth
Erick Almaraz wrote:Dear Ruth.

The use of the wa.dat is optional. If you want to use it, you must give a .dat file containing the values of the factor scale and the equation of state for each a, ie, (a,w(a)).

Regards

help to use ppf module

Posted: October 29 2014
by Erick Almaraz
Yes, you can specify the functional form of your favourite parametrization. For that purpose, in the function w_de(a) you could find the next lines:

if(.not. use_tabulated_w) then
w_de=w_lam+wa_ppf*(1._dl-a)

where w_lam and wa_ppf are constants whose values are imported from the .ini file. Anyway, here you can modify the parametrization, bearing in mind that you have to do extra changes in case you are handling more than two parameters.

Regards