GNUPlot
Availability: Labs | Free Download Comparable: GNUPlot is a command-line program that can generate two- and three-dimensional plots of functions, data, and data fits.
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Graphical Analysis
Availability: Labs | Download Comparable: Geometer’s Sketchpad Graphic Analysis is a low-cost, downloadable graphic software program created by Vernier. This program is designed to help the user create, analyze, and learn about graphs. The software is both available for Windows and Mac devices.