DistributionParameterQ

DistributionParameterQ[dist]
yields True if dist is a valid distribution, and yields False otherwise.

DistributionParameterQ checks that numeric parameters meet parameter assumptions for the input distribution dist and assumes symbolic parameters are valid.

DistributionParameterQ issues a message when it encounters an invalid parameter.

Check a normal distribution with valid parameters:

A normal distribution with invalid standard deviation:

Check a normal distribution with valid parameters:

Out[1]=

A normal distribution with invalid standard deviation:

Out[2]=

Test distributions with combinations of numeric and symbolic parameters:

Check valid univariate and multivariate discrete and continuous distributions:

Check invalid distributions:

Test a constructed distribution:

A data distribution:

Define a function for valid distributions:

The function evaluates on a distribution:

It returns unevaluated for other inputs:

DistributionParameterQ assumes symbolic parameters are valid:

DistributionParameterAssumptions returns conditions on parameters:

With numeric parameters, the outputs are equivalent: