I have some long functions with about half a dozen varibles. Some thing like: f(t) = sqrt((Gr^2*Gw^2+Gr^2)*cos(Gw*t)^2 -2*Gr*Xr*Xw*cos(Gw*t) +Xr^2*Xw^2) I want to define the variables, then plot out the curves, integrate an interval, then change some variables and re-plot the curve, and re-integrate. Making an input file that defines the variables and the function along with the integration command would be fine, I'm thinking that Octave would probably be the app for that. I could use an outline of how to do that. I have Octave, GnuPlot, and SciDAVis. I was hoping to use SciDAVis, although I am having trouble figuring out how to define the variables. What should I do?