NR3 Webnotes are short sections that extend the main text of Numerical Recipes (Third Edition). They are referenced in the sections of the book that they pertain to.

The NR3 Dependencies Tool figures out exactly which .h files (and in which order) you need to include, based on routines that you are using.

Confused about which NR3 routines are in which .h files, or in which chapters, sections, or pages? Use the Dynamic Index of Routines tool.

You can call Numerical Recipes routines (along with any other C++ code) from Python. A tutorial with examples is here. A free interface file is here. These files are a bit out of date, so you might have to do some experimenting.

Check out the JavaScript enabled Julian Day and Civil Date Calculator. If you like it, feel free to copy its source code to your own Web page. This page uses JavaScript ports of the NR routines caldat and julday and does not require any CGI script at the server end!

An ambitious NR3 user translated nearly all of the Third Edition C++ code into Java. That code is included in the purchased download of the NR3 C++ code. Please see further information here.

If you are interested in time-series, check out the Fast Statistical Methods Page. It contains links and public-domain code for some interesting techniques.

When you need mathematical software that can be freely redistributed as source code (which Numerical Recipes can't), a good place to look is Netlib. Within Netlib, the SLATEC package offers a comprehensive collection of (alas, Fortran only) source code.

• Netlib distribution site
• SLATEC index page

Many Numerical Recipes readers are also interested in the Chemehuevi language ;)

• www.chemehuevilanguage.org.

Interested in Albrecht Dürer's magic square, as featured in the Dan Brown book?

• Did Dürer Intentionally Show Only His Second-Best Magic Square?

Interested in the principles behind moving averages (a.k.a. sliding window averages)?

• Principled Derivation of Some Moving Average (Sliding Window) Statistics

Interested in how Large Language Models like ChatGPT or GPT-4 actually work?

• Slides from talk: How Does Generative AI Actually Work (a quick introduction to Large Language Models)