Missing sqrt

[andreasnoack]

julia> sqrt(BFloat16(1.0f0))
ERROR: StackOverflowError:
Stacktrace:
 [1] sqrt(::BFloat16) at ./math.jl:518 (repeats 80000 times)

[ViralBShah]

Do we not have a generic sqrt implementation somewhere? Perhaps @pkofod has one?

[ViralBShah]

We can also just use @alanedelman 's Babylonian sqrt demo from his AD notebook.

[pkofod]

Not too familiar with this number type. From the readme it seems like it’s okay if it calls the Float32 sqrt (insofar that doesn’t calculate stuff in Float64) and convert back to BFloat16? If that’s the case then this is just the issue that’s popped up a few times, that the fun(x::Real)=fun(float(x)) fallbacks can cause infinite recursion when float(x)=x.

[andreasnoack]

It looks like #3 might be useful here. It looks like most of the standard float functions are currently missing.

[ViralBShah]

I think doing enough to get a cholesky/svd working would be useful without going crazy over the full list.