DPlot

That works much better. It still isn't an exact size but I can see how you can play around with the variables.

Thanks, you've been really helpful!

Thanks for the prompt reply.

I can produce a really nice grid with the thicker intermediate lines, so thanks for that!

Do you know why, when I specify a width of 160mm it prints as 149mm wide and a height of 280mm it prints as 261mm?

Is it possible to plot algebraic or trigonometric x-y graphs where you can specify the grid intervals, as though you were drawing the graph on graph paper?
I would like to plot with a grid of 2mm width squares on A4 paper so that students could work out the gradient of the curve at various points ...