While the bc command is extremely well known, there's little awareness of its competitor Spigot. Nevertheless, all it takes is a quick read of the manual and a few sample sums to start using this simple tool. The program borrows its name from the eponymous algorithm for calculating mathematical constants. However, there are other programs with the same name, which can be rather confusing. The software was developed by Simon Tatham [1].

The source for Spigot is available from [2], but you are better off simply installing it with your trusty apt software manager:

sudo apt install spigot

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