plot
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plot can do simple x-y plots, can overlay two x-y plots, can draw histograms, can do scatter plots, and can draw contour or pseudo-color representations of your matrices (supporting bicubic interpolation for small matrices and plotting of both positive and negative contours).
Enough with that, let's get down to business: here is the tutorial with plenty of screenshots. Get the compressed archive plot-v.1.3.tar.gz (1.5 MBytes). The distribution includes source code, documentation and pre-compiled executables suitable for Linux and MacOS.
Spherical harmonics
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and it allows you to change the values of the parameters (A,B,C,D,E,F,G,H) while observing the effects of your changes. Download the linux executable (don't forget to chmod it) or the source code (sph.c) which you can compile with something in the spirit of cc sph.c -lglut -lGLU -lGL -lXext -lX11 -lm
Fourier for hp48
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Pepinsky's machine
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Get the compressed archive pepinsky.tar.gz (3.1 MBytes). The distribution includes source code, documentation, example scripts, a couple of exercises and pre-compiled executables suitable for Irix, Linux, OSF and solaris. Get also this newer linux executable.
You can get Pepinsky's machine running smoothly on Windows 10 through the bash interface. Follow this guide, then type 'pepinsky' from the windows bash shell and you should see it.
mcps
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Get the compressed archive mcps.tar.gz (812 KBytes). The distribution includes documentation (manual page, html) and pre-compiled executables suitable for Irix, Linux, OSF and solaris.