Add ICDF and CDF to BernoulliProbs #1652
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I was using
numpyro
for a particular application which required an ICDF and CDF for a Bernoulli, however this was not yet implemented.I use Heaviside functions to calculate the CDF and ICDF. Tests are a little more complicated, as for a Bernoulli one doesn't recover the original quantiles when passing uniform samples through an ICDF, and then back through a CDF. I added a few specific lines for the Bernoulli such that the mean of ICDF(quantiles) is roughly equal to the probability parameter for the bernoulli. To test the CDF, I check that the proportion of ones yielded through CDF(ICDF(quantiles)) is roughly equal to p, and that the proportion of (1 - p) values through the same function is roughly equal to (1 - p).