In Julia has anyone implemented the normal distributions pdf or cdf to support arbitrary precision BigFloats.
For example this code returns 0.0, when in fact the values should be slightly different.
x = parse(BigFloat, "2.1")
x_small = float64(x)
pdf(Normal(), x) - pdf(Normal(), x_small)
Not directly. My eventual plan is to make Distribution types parametric, which would also allow for Float32
arguments, but that is a while away yet.
In the meantime, there is the non-exported φ
which gives the result you wanted:
Distributions.φ(x) - pdf(Normal(), x_small)