Discrete Epigram for the Histogram for GP/PARI (Episode #2) 

One Minute One-liners for the curious: https://www.youtube.com/@1minute1liners

In this YouTube short, I explain how to create a fast discrete histogram function that can count all manner of datatypes in PARI, including finite field elements, polynomials, polymods, rational functions, etc. The one-liner of note is:

SX=vecsort(X,cmp);

Below are the functions discretehist.gp and its test code tdiscretehist.gp, as well at inthist.gp and the test code tinthist.gp

The 7 support functions in tdiscretehist.gp are as follows:

• pause(t) - wait for t seconds

• false(N) - create vector of N zeros

• binequal(a,b) - create binary vector indicating where vectors a and b are equal

• binrand(N) - create binary random vector

• binrand0(N) - create binary random vector not all zero

• vecidiff(a) - crete binary vector indicating where values change

• idxzero(a,{b=0}) - create index vector indicating where a==b