I just received the 4th edition copy of Physically Based Rendering[0].
Donald Knuth wrote "This book has deservedly won an Academy Award.
I believe it should also be nominated for a Pulitzer Prize."
It is a 1200 page literate program. It not only contains the actual
source code, it contains complete explanations of the physical theory
and the implementation ideas. This textbook is used in a various
upper-class and graduate programs. I can highly recommend it.
I had hoped that Axiom could have been reborn as a literate program.
The idea was to "make it live beyond the authors". Each algorithm
would provide an explanation, various literature references, and some
examples as well as limitations. That way a person with no background
knowledge in computer algebra could learn and contribute. Such a
literate program would have set the standard for mathematical software.
Sadly that's not going to happen.
Tim
[0] Matt Pharr, Wenzel Jakob, and Greg Humphreys "Physically Based Rendering"