# Talk:Pythagorean addition

Good find, David Eppstein. I have encountered the term "addition in quadrature" many times in signal processing but never "Pythagorean addition". They do refer to the same things, so a merge is warranted. Cheers, cmɢʟee⎆τaʟκ 22:03, 3 May 2021 (UTC)

Hypot and Alpha max plus beta min algorithm are also on more or less the same topic. We might consider merging them in as well, or at least using Wikipedia:Summary style to integrate pointers to them into the main article text instead of just listing them under see-also. —David Eppstein (talk) 23:28, 3 May 2021 (UTC)
Note: http://books.google.com/ngrams/graph?content=Pythagorean+addition%2Caddition+in+quadrature%2Cbeta+min%2Chypot&year_start=1820&corpus=26 gives relatives frequencies found in Google Books (year starting 1820 as earlier years have unusually high occurrences of hypot). Hypot takes the lead, though it might be a contraction of hypothesis. Addition in quadrature seems much more common than Pythagorean addition or beta min (the entire phrase was not found). Add in quadrature is even more frequent, but I used addition as a fairer comparison to Pythagorean addition. cmɢʟee⎆τaʟκ 00:56, 7 May 2021 (UTC)
Support merge: Pythagorean addition focusses on the mathematical function, while the Addition in quadrature article primarily discusses the application of this process to signal processing (and error propagation more generally). I think that pattern reflects use too. Perhaps we also have a difference here between mathematical literature and more prevalent engineering/physics literature. On balance, I'd be tempted to merge to Pythagorean addition, giving Addition in quadrature as a synonym in the context of signal analysis and error propagation, the use supported in the references for the latter article. The Noise section can then be included in an Applications section. I think that the ngram for hypot might well be showing contractions for hypothesis and hence has misleading weight. Klbrain (talk) 18:38, 4 October 2021 (UTC)