Please don't fall into the trap of believing that I am terribly dogmatical about [the go to statement]. I have the uncomfortable feeling that others are making a religion out of it, as if the conceptual problems of programming could be solved by a single trick, by a simple form of coding discipline!
A library for numerical calculations with multivariate polynomials. This Python script confirms Euler’s four-square identity (in 0.02 seconds):
import time from mvpoly.dict import * t0 = time.time() a1, a2, a3, a4, b1, b2, b3, b4 = MVPolyDict.variables(8) p = (a1**2 + a2**2 + a3**2 + a4**2) * (b1**2 + b2**2 + b3**2 + b4**2) q = (a1*b1 - a2*b2 - a3*b3 - a4*b4)**2 + \ (a1*b2 + a2*b1 + a3*b4 - a4*b3)**2 + \ (a1*b3 - a2*b4 + a3*b1 + a4*b2)**2 + \ (a1*b4 + a2*b3 - a3*b2 + a4*b1)**2 assert p == q, "failed Euler-Goldbach" t1 = time.time() print("%8.6f" % (t1 - t0))
The Octave package can be installed using the command
sudo octave --eval "pkg install mvpoly-octave-0.97.9.tar.gz"
For the Matlab package, see the included README for installation instructions.
sudo pip install mvpoly
NetBSD users can install the Python package
The package source can be found on the GitLab page.