[rrd-users] Plotting a derivative of gauge data

[Aleksandr Pasechnik]

Hello,

I have some temperature data stored and I would like to plot the derivative to observe the rate of change. I can't seem to find anything along the lines of a derivative function in the rpn documentation. Can it be done? How might one go about calculating the derivative? I suppose a simple diff would work, if I took the stack, and subtracted a stack shifted by one it would give me what I need, but I was hoping for a built in function of some sort.

Thanks!
Al