[dunefox]

Did you launch Julia for each image separately?

[enriquto]

Yes. I was using julia as a shell calculator to multiply small matrices. Octave happens to be much faster for this (admittedly niche) use case.

[bluenose69]

Working this way is pretty common for small tasks. As has been suggested, Julia 1.9 is a lot faster than it was before. I find it's more like 4 seconds than 0.5 seconds, though.

With plot.jl as

    $ cat plot.jl
    using Plots
    x = range(0, 10, length=100)
    y = sin.(x)
    plot(x, y)

I find that

    $ time julia plot.jl

yields

    4.19s user 0.50s system 106% cpu 4.409 total

[enriquto]

Plotting is a complicated beast. If you just want to multiply matrices, there's no "using" statement and you get sub-second running times. Still geologically slow, but at least somewhat manageable.