Meshgrid vs. array broadcasting

test.jl

using Plots

meshgrid(x,y) = (repmat(x',length(y),1),repmat(y,1,length(x)))

function test_meshgrid(n)
  n = Int(n)
  x = linspace(0,2pi,n); y = x
  ret = zeros(n,n)
  tic()
  X, Y = meshgrid(x,y)
  for j = 1:n
    for i = 1:n
      ret[i,j] = sin(X[i,j] + sin(Y[i,j]))
    end
  end
  toc()
end

function test_broadcast(n)
  n = Int(n)
  x = linspace(0,2pi,n)'
  y = x'
  tic(); ret = sin(x .+ sin(y)); t = toc()
  t
end

plot(floor(logspace(1,3)),[test_meshgrid,test_broadcast],
     labels=["meshgrid","broadcast"]',title="elapsed time")
savefig(dirname(@__FILE__)*"\\mesh_v_broadcast")

meshalloc(n) = @allocated test_meshgrid(n)
broadalloc(n) = @allocated test_broadcast(n)
plot(floor(logspace(1,3)),[meshalloc,broadalloc],
     labels=["meshgrid","broadcast"]',title="memory allocation")
savefig(dirname(@__FILE__)*"\\mesh_v_broadcast_malloc")