Is there a quick way to create an 3x1 Array{ T , 2} where T is a type ? [A, B, C, ...] or [A; B; C; ...] construct a 1-d array (vector). [A B C ...] constructs a 2-d row array. What about a 2-d column array? Does anyone know why [A; B; C; ...] wasn’t chosen for this task?

Julia 1.7 allows julia> [1; 2; 3; 4 ;;] 4×1 Matrix{Int64}: 1 2 3 4

See this discussion for multiple suggestions (depending on whether you want to construct from existing contents, etc): [image] How to force single column array? General Usage Hey guys, I want to make an array with only a single column, so ie. something like 4x1 Array{Int3…

I guess reshape is the way to go, but intuitively I think [A; B; C] makes a lot of sense and would also remove the issue of two different syntaxes doing the same thing.

[image] 4aHxKzD: the issue of two different syntaxes doing the same thing. [A, B] and [A; B] don’t do the same thing, though: julia> A = [1, 2, 3]; B = [4, 5]; julia> [A, B] 2-element Array{Array{Int64,1},1}: [1, 2, 3] [4, 5] julia> [A; B] 5-element Array{Int64,1}: 1 2 3 4 5

Didn’t think about that, thanks.

I think that the cheapest solution, with the same cost as creating a vector, is hvcat: julia> using BenchmarkTools julia> @btime [1,2,3] 34.418 ns (1 allocation: 112 bytes) 3-element Array{Int64,1}: 1 2 3 julia> @btime reshape([1,2,3],:,1) 101.557 ns (3 allocations: 208 bytes) 3×1 Array{In…

Construct a 2-d column array

General Usage

Tamas_Papp November 2, 2019, 12:37pm 2

See this discussion for multiple suggestions (depending on whether you want to construct from existing contents, etc):

Topic		Replies	Views
How to create a 2x1 Array? New to Julia	51	7639	May 13, 2023
How do I create a 1,2,3 3x1 Matrix? New to Julia	21	2174	May 20, 2021
Creating Column Matrix with Array Literals General Usage array	4	613	January 21, 2021
How to force single column array? General Usage	31	5452	July 25, 2019
Why does [1; 2; 3] creates an Array of dimension 1 instead of 3x1 Array of dimnesion 2 General Usage array	7	1452	May 31, 2018

Construct a 2-d column array

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