Problem with python vs fortran getdist

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Sunny Vagnozzi
Posts: 55
Joined: August 15 2016
Affiliation: Kavli Institute for Cosmology (KICC), University of Cambridge

Problem with python vs fortran getdist

Post by Sunny Vagnozzi » August 24 2017

Hi Antony et al.,

recently I switched from using the fortran version of getdist to using the python one. However, I noticed differences between the results produced by the two. Specifically, the triangle plots I obtain after analysing chains with the Python version are sometimes quite different. Please see the files fortran.pdf and python.pdf where I compare the results obtained after using the fortran getdist and the python getdist respectively (same distparams.ini, same chains)!

By the way, the python getdist gives me the following warning

Code: Select all

RuntimeWarning: divide by zero encountered in divide
  corrected = (bins2D[ix] * A + xP * Ax + yP * Ay) / denom
whereas the fortran version does not.

Any ideas on what is causing this and how to solve it?

Cheers,
Sunny

Antony Lewis
Posts: 1936
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

Re: Problem with python vs fortran getdist

Post by Antony Lewis » August 24 2017

Are you using the latest getdist python version?

Sunny Vagnozzi
Posts: 55
Joined: August 15 2016
Affiliation: Kavli Institute for Cosmology (KICC), University of Cambridge

Re: Problem with python vs fortran getdist

Post by Sunny Vagnozzi » August 24 2017

Antony Lewis wrote:Are you using the latest getdist python version?
Yep, downloaded the latest version. Not sure what's going wrong though.

Antony Lewis
Posts: 1936
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

Re: Problem with python vs fortran getdist

Post by Antony Lewis » August 24 2017

If you can email me a link to the chains I can have a look at what's going on with the bottom-left plot.

Sunny Vagnozzi
Posts: 55
Joined: August 15 2016
Affiliation: Kavli Institute for Cosmology (KICC), University of Cambridge

Problem with python vs fortran getdist

Post by Sunny Vagnozzi » August 24 2017

Thanks, I've just sent you an email but if can be useful for anyone else, here is a public link to the chains and distparams.ini used: https://uploadfiles.io/nrg8f

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