GraphPower is a function grapher that runs on your computer. There are versions for Mac OSX 10.5+ or Windows XP/Vista, it’s available for $10 (after discount) from www.graphpower.com.
Features include
- cartesian (x-y) graphs, polar graphs and parametric curves
- integration, including arclengths and surface and volumes of revolution
- multiple plots on the same window
- export plots to a PNG image file
- full control over plot colors