fix fallback for scaling blas number with array #17739
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| @@ -18,6 +20,8 @@ function scale!{T<:BlasFloat}(X::Array{T}, s::T) | |||
| X | |||
| end | |||
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| scale!{T<:BlasFloat}(s::T, X::Array{T}) = scale!(X, s) | |||
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why does this method exist? really strange to be sometimes mutating the second input, but usually the first
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Perhaps to be symmetric like multiplication?
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Because multiplication is not always commutative.
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I also thought it was weird. I guess it is there for non commutative numbers in the general case.
Edit: Beaten to the punch
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mutating methods need to be consistent about what they're mutating.
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No they don't. We don't agree here and for those of us who use this method, it doesn't cause trouble.
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It's mutating the array, whichever argument that is.
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Added to #16772. Being explicit with 3 arguments seems like a much more predictable API when you're writing generic code that has to deal with various combinations of input types.
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Apple seemed to got stuck on something unrelated. Since this should be fairly uncontroversial I'm gonna click the scary button for the first time. 🎉 |
Also adds a fast path for special case of zero and one.
JuliaLang/LinearAlgebra.jl#351