AudioScope is a text mode audio oscilloscope that captures sounds using DEMO, SOX, or DSP (/dev/dsp}. It is primarily a learning tool for kids. The script includes code and circuit diagrams for calibrating the horizontal and vertical axes. It features a demo mode with no dependences that samples /dev/urandom.
The Advanced Bash Scripting Guide is both a reference and a tutorial on shell scripting. This comprehensive book, the equivalent of 1,000+ print pages, covers almost every aspect of shell scripting. It contains 382 profusely commented illustrative examples, a number of tables, and a cross-linked index/glossary. Not just a shell scripting tutorial, this book also provides an introduction to basic programming techniques, such as sorting and recursion. Included scripts are the Game of Life, a Perquackey variant, a Morse code trainer, and an implementation of the Gronsfeld Cipher. This book is suited for both individual study and classroom use. It covers Bash, up to and including version 4.2. Note that users of miniaturized single-board computers running Linux, such as the Raspberry Pi and the Beagle Bone, would find this Guide useful for learning and running Bash scripts to explore and expand the capabilities of these small, but powerful machines.
SCaVis is an environment for scientific computation, data analysis, and data visualization designed for scientists, engineers, and students. The program can be used for function and data plotting in 2D and 3D, histograms, statistical analysis, and symbolic calculations using the Matlab/Octave high-level interpreted language.
PHP Debug is single API for tracing PHP applications. With a single file of only 200 lines, you can add, with minimal impact, diagnostics to be displayed upon program termination. Each diagnostic contains file, function, and caller function information. You just need to include the debug.php file and add debug() calls throughout your code in the same way as var_dump(). The diagnostic messages are stored and displayed in a list. Diagnostics can be disabled and controlled. It's small and simple yet very versatile.
The Version numbers read/write command line tool finds and updates version number tokens in source code or packaging files. It takes filename context and syntax into account for reading and writing to files. It provides an easy and readable argument format, and can increase patch versions or bump build numbers. It's a minor simplification for manual package building.