Add rms (root-mean-square) function

[acxz]

I think it would be a good idea to have a rms function in stats.

If this is a feature that would be welcome, I'd love to try my hand at contributing this.

[rikhuijzer]

There are a whole lot of measures already available in pure Julia via MLJBase.jl. Docs are at https://alan-turing-institute.github.io/MLJ.jl/v0.3/measures/ and source at https://github.com/JuliaAI/MLJBase.jl/tree/dev/src/measures:

julia> using MLJBase

julia> rms(1:3, 2:4)
1.0

[nalimilan]

Isn't rmsd what you're looking for? https://juliastats.org/StatsBase.jl/latest/deviation/#StatsBase.rmsd

[acxz]

rmsd is exactly what I'm looking for. I tried searching just rms and didn't get any hits from the github search I apologize, shouldve looked deeper into the docs. Thanks @nalimilan !