Usage¶

• Code input/output:

  The adopted configuration and the progress of the run are shown on the screen if the option screen-output=1 is added inside the [input] section of the configuration file. Otherwise, the output from pyRing is stored in the example_outdir/stderr_pyRing.txt, example_outdir/stdout_pyRing.txt files, while the progress of the sampler is stored inside the Nested_sample/cpnest.log file. Data and PSD diagnostic plots are produced at the beginning of the run and can be found in the example_outdir/Noise directory. All paths in the configuration files are relative to the path stored in the PYRING_PREFIX.

  At the end of the run, the posterior and evidence files can be found in the example_outdir/Nested_sampler directory under posterior.dat and Evidence.txt. Results on all parameters are displayed in the example_outdir/Plots directory. If the pesummary option is activated (see the help message for details), a PESummary metafile containing all the necessary information to reproduce the run, together with the complete run output, will be produced. Also, an html page displaying parameters posteriors will be created under: example_outdir/Plots/pesummary_postproc/home.html.

• Sampler convergence:

  For details on the sampler used, CPNest, see CPNest documentation.

  Standard templates with a small number of parameters (e.g. a single damped sinusoid or a single Kerr mode) can be safely employed with the sampler settings documented in the repopath/pyRing/config_files/config_gw150914_production.ini example.

  When assuming many Kerr modes (e.g. more than two overtones), care must be taken in assessing the sampler’s convergence. To produce publication level results in these cases, we suggest checking that more conservative sampler settings such as nlive=8192, maxmcmc=8192 do not change the obtained results. We also suggest combining at least four parallel chains.