DenseArrays.jl

Experimental package with the goal of producing a central type of vectors that are:

Type	Description
FixedImmutableVector	immutable with fixed length
StaticImmutableVector	immutable with length known at compile time (static)
FixedMutableVector	mutable with fixed length
StaticMutableVector	mutable with length known at compile time (static)

The only multidimensional array type is DArray, which is a dense array that wraps any one of these vectors (or Base.Vector). An N dimensional DArray has N axes to providing shape. The product of the lengths of all axes is equal to the length of the underlying data vector.

julia> using DenseArrays

julia> function element_index_test(x)
           for i in rand(1:length(x), length(x))
               x[i]
           end
       end

julia> dynamic_vector = rand(200);

julia> fixed_immutable_vector = FixedImmutableVector(dynamic_vector);

julia> @time element_index_test(dynamic_vector)
  0.021871 seconds (43.95 k allocations: 2.228 MiB)

julia> @time element_index_test(dynamic_vector)
  0.000005 seconds (1 allocation: 1.766 KiB)

julia> @time element_index_test(fixed_immutable_vector)
  0.011446 seconds (14.78 k allocations: 781.453 KiB)

julia> @time element_index_test(fixed_immutable_vector)
  0.000006 seconds (1 allocation: 1.766 KiB)

Some constructors...

julia> FixedImmutableVector(1, 2, 3);

julia> FixedImmutableVector([1, 2, 3]);