Introduction

This book describes plt, a non-interactive plotting utility originally written for Unix by Paul Albrecht. plt can produce publication-quality 2D plots in PostScript from easily-produced text or binary data files, and can also create screen plots under the X Window System. Compared to most other software for 2D graphics, plt has several significant advantages:

• plt generates compact vector PostScript output, which can be transmitted quickly yet can be resized without introducing raster artifacts.

• plt works well with a wide variety of tools that create and manipulate readable text files.

• plt is scriptable; if you need to make 100 plots of 100 data sets, you don't need to point and click for hours.

• Complex overlays and multi-part plots are easy to make, using multiple invocations of plt to write to a single window or page.

• plt can read data from a pipe, so it can be used to observe real-time signals or the outputs of computationally intensive processes as they become available.

• plt imposes no fixed limits on the number of points in a plot (even the total amount of available memory is not a constraint if the data are read from a pipe and the axis limits are pre-specified).

• plt is free, open-source software that can be modified as needed for unique applications. (plt can be compiled under GNU/Linux, Mac OS X, MS-Windows, or any version of Unix.)

• plt is easy to pronounce (say: P-L-T) and is almost as easy to spell :-)