I’ve read that when I declare an array like this: a = [1,2,3,4,5] it can be slower, but why? Is it because Julia has to determine the type? Can it be slower when you don’t provide the dimensions of an array? For example, is this: a = Array{Int32}(undef, 5) faster then this: b = Int32[]

[image] anon60034542: When no type or values are provided and it defaults to Any, it’s slower? Yes, an Any[] array tends to be slower to compute with than an array with a concrete element type, like Int[].

Why is it slower when you declare an array like this?

New to Julia

kristoffer.carlsson October 8, 2020, 2:45pm 11

Yes, an Any[] array tends to be slower to compute with than an array with a concrete element type, like Int[].

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Why is it slower when you declare an array like this?

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