I have observed the following type instability when using reduce + hcat as follows (see examples below). Is this intended? Could it be related to issue#46331 ? More context: I am using this syntax, as recommended here ., when converting a Vector of scalar or arrays into a higher-dimensional array (e.…

I think you want stack. The earlier magic methods of reduce(hcat, xs) are quite specific, and your example isn’t hitting them. It is just doing hcat(1.0, 1.0), hcat(hcat(1.0, 1.0), 1.0) and so on. Combining elements zero times returns just 1.0. julia> @which reduce(hcat, ones(4)) reduce(op, A::Abs…

Thanks! I just independently found out about stack indeed :slight_smile:

Quick note: stack does not seem to work well with Vector{String} input: julia> stack(["hello", "world!"]) ERROR: MethodError: no method matching size(::String) Stacktrace: [1] axes(A::String) @ Base ./abstractarray.jl:98 [2] _stack_size_check @ ./abstractarray.jl:2870 [inlined] [3] _typed…

That’s a bug, I think, but a bug in the error-printing function. stack claims to accept any iterator of iterators, but all the inner ones must have the same size. julia> stack(["hello", "world"]) 5×2 Matrix{Char}: 'h' 'w' 'e' 'o' 'l' 'r' 'l' 'l' 'o' 'd' julia> stack(["hello", "world!"]) …

Reduce + hcat is type unstable

General Usage

mtanneau April 10, 2024, 8:59pm 3

Thanks! I just independently found out about stack indeed

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Reduce + hcat is type unstable

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