It’s a long and pointless enumeration, but given that you ask… C, Pascal, Prolog, Standard ML, Scheme, Snap!, Basic, Python, Java (medium fluency, def not a professional developer), and several more for toy projects.
Thanks for suggesting that implementation of Ramer-Douglas-Peucker. I’d seen that alg applied to time series.
In any case, my original post was more about finding a body of code I could go through. For some languages, understanding the sources to their standard library is good practice; for others, there’s some book or writeup with good code, and so on. I don’t know where to find that for p5
Cheers