plot_mpi.jl

function plot_fields(mesh, rank, proc, field, xp, yp, iplot)

    dx, dy = mesh.dx, mesh.dy
    ix, jx = 1, mesh.nx + 1
    iy, jy = 1, mesh.ny + 1

    if iplot == 1
        mkpath("data/$rank")
    end

    io = open("data/$(rank)/$(iplot)", "w")
    for j = iy:jy
        for i = ix:jx
            @printf(io, "%f %f %f \n", xp + (i - 0.5) * dx, yp + (j - 1) * dy, field[i, j])
        end
        @printf(io, "\n")
    end
    close(io)

    # write master file

    if rank == 0

        if iplot == 1
            io = open("bz.gnu", "w")
            #write(io, "set xr[-0.1:1.1]\n")
            #write(io, "set yr[-0.1:1.1]\n")
            write(io, "set zr[-1.1:1.1]\n")
            write(io, "set surf\n")
        else
            io = open("bz.gnu", "a")
        end
        write(io, "set title '$(iplot)' \n")
        write(io, "splot 'data/$(rank)/$(iplot)' w l")

        for p = 1:proc-1
            write(io, ", 'data/$(p)/$(iplot)' w l")
        end
        write(io, "\n")
        #write( io, "set term gif \n")
        #write( io, "set output 'image$(lpad(iplot,3,"0")).gif'\n")
        #write( io, "replot\n")

        close(io)

    end

end