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cosmosis / samplers / apriori

The Apriori sampler

Explore points from given distribution

Name: Apriori

Version: 1.0

Author(s): CosmoSIS Team




The apriori sampler chooses successive points in parameter space, independently of each other, from the a priori distributions of the parameters decreed by the values.ini file (more specifically, the file referred to in the [pipeline]/values item of the .ini file given to cosmosis).

Along with the grid and star samplers, the outputs can be inspected to reveal the overall shape of the likelihood surface, and the distribution of output sample points should provide an indication that the a priori parameters╩╝ sample distribution is reasonable and workable.


No special installation required; everything is packaged with CosmoSIS


These parameters can be set in the sampler's section in the ini parameter file.
If no default is specified then the parameter is required. A listing of "(empty)" means a blank string is the default.

Parameter Type Meaning Default
nsample Integer Very simply, the number of samples, and consequently runs of the Cosmosis pipeline and lines in the output file, that are drawn from the prior distribution.