GNUplot

GNUplot is described as "a portable command-line driven interactive data and function plotting utility for UNIX, IBM OS/2, MS Windows, DOS, Macintosh, VMS, Atari and many other platforms." The software, which is copyrighted but also freely distributed, was designed to allow scientists and students to visualize mathematical functions and data. Since its development, GNUplot has also proved useful in supporting many non-interactive uses, such as Web scripting and integration as a plotting engine for third-party applications. The plots can be either 2-D or 3-D, using lines, points, boxes, contours, vector fields, surfaces, and various associated text. The current officially released version of GNUplot is available to download from this website. Also available are minimal instructions for building from CVS source, instructions for patching and building, and a demo gallery along with other documentation. Visit the website