Octave, a freely downloadable alternative to Matlab, mostly compatible. For Windows, Macintosh, and Linux.



SPECTRUM, simple, freeware, 90s-era signal processing program, for Macintosh OS 8.





Microsoft Excel 2013 OpenOffice Calc 4.1.1



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Copyright (c) 2020, Thomas C. O'Haver (toh@umd.edu)



Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:



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A Brief History of Mine

(Mining the literature using the Google Books Ngram Viewer)

Digital began to pull away from analog in the 1950s and now completely dominates.

In the mid 1990s, Web sites began to dominate earlier publishing technologies.

Transistors, invented in the late 1940s, pulled ahead of vacuum tunes in the 50s. By the early 80s, integrated circuits chips were dominant.

Statistics and quantitative signal and data processing have long been important, using computers after the 1950s.

"Derivative", "smoothing", and "convolution" are old concepts, but other signal processing terms don't become common until more recently.

The most common derivative orders have long been the first and second; higher older are much less used.

The Savitzky-Golay smooth is now the most often mentioned data smoothing technique. (What was going on the "triangular smooth" in the 1800s?)

The Gaussian profile is the most commonly encountered peak shape.

Measures of precision in the presence of random noise increased with the availability of electronic instrumentation.