A Pragmatic* Introduction to Signal
with applications in scientific measurement
An illustrated essay with free software and spreadsheet
templates to download
Last updated July 23, 2022.
A retirement project created
and maintained by
Tom O'Haver ,
Professor Emeritus, Department of Chemistry
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* Pragmatic: Relating to matters of fact or practical affairs,
often to the exclusion of intellectual or artistic matters;
practical as opposed to idealistic.
Software used in this essay
high-performance commercial numerical computing environment and
programming language that is widely used in research and
education. For Windows, Macintosh, and Linux. Lower-cost
Home and Student versions available.
Octave, a freely
downloadable alternative to Matlab, mostly compatible. For
Windows, Macintosh, and Linux.
a fast and free general purpose language for Windows, Unix, and
Microsoft Excel 2013
OpenOffice Calc 4.1.1
Thanks to M. Farooq Wahab for his many
contributions and for many fruitful discussions, to
Baldassarre Cesarano for his close reading and typographical
correction of this text, to Dr. Raphael Attie of NASA/Goddard
Space Flight Center for corrections, to Diederick of The
University of Hong Kong for code contributions, to Yuri
Kalambet of Ampersand Ltd. for mathematical insights, and to the
many email correspondents who have made suggestions, asked
questions, caught errors, and have shown me new types of data
and new applications that have broadened the scope of this
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First edition created in
1995. Last updated July, 2022. Created with SeaMonkey.
This site is a retirement
project and international community
service, created and maintained by Prof. Tom O'Haver,
Professor Emeritus, Department of Chemistry and
Biochemistry, The University of Maryland at College
Park, currently residing in Naples, FL. Comments, suggestions
and questions should be directed to Prof. O'Haver at firstname.lastname@example.org,
currently residing in Naples, FL, and in Silver Spring, MD.