Does anyone know of a good calculus application (preferably GPL), I need it to be able to indefinite differentiation/integration mostly (and definite while I'm at it) but more advanced functions will be needed sooner or later. Graph plottingfacility would be a bonus (i'm currently using gnuplot which is excellent at its job but it is handy to have one application for all my function manipulation needs).

thanks in advance

MATLAB, but it costs money, is a good maths program that runs on Linux.
There is also scilab, which is free and open source, but IMHO is not as good as Matlab.

I don't know if they will do symbolic integration, but they probably do numerical integration. For symbolic integration/differentiation, perhaps it is better to learn to do it by hand?

--Ian

The only free package I know of with this sort of capability is GNU MAXIMA:

http://maxima.sourceforge.net/

REDUCE (http://www.uni-koeln.de/REDUCE/) is not free, but is supposed to be quite cheap.

Neither is likely to be serious competition for Maple or Mathematica, if that's what you're hoping.

I mainly want this software for mostly checking I've got my sums right, I can easily do it by hand but I have a bad tendency to lose the odd minus here and there (is there anyone who actually needs this functionality who can't integrate). My main use for any calculus would be for when I'm writing up various bits and pieces I won't make a mistake, plus it would be nice to have it in a format fo cut&pasting (tho I know this is unlikely), this is no problem tho as OO Math Edit is a wonderful bit of kit.

I'm compiling maxima as we speak so I'll let you know how I go