negative number raised to even power

[Claudio L.]

(05-07-2015 10:40 AM)Gerald H Wrote:  Lotus 123, 2.4: aba

Historically, this seems interesting.
Visicalc (the very first mass-market spreadsheet) introduced the idea of -2^2=4 into spreadsheets. Lotus 1-2-3, despite being an "imitation", went with -2^4=-4, knowing this was breaking compatibility with Visicalc.
A few years later, Excel followed the Visicalc path, even though Lotus was the market leader and the one to be "imitated", reintroducing -2^2=4 into the spreadsheet world.
Quatto Pro kept the Lotus way for compatibility, but eventually MS crushed the competition and every other modern spreadsheet since then has been copying -2^2=4 to keep their precious Excel compatibility.
Everything else in Wes's list agrees on -4, so it seems one bad apple turned all spreadsheets down that path. Question remains whether the bad apple was Visicalc or Excel. I'd think Excel, since at the time Lotus had already steered the world towards -4.