# Tag Info

is about calculations in (La)TeX documents. A popular package is `calc` that redefines most length- and counter-setting macros (like `\setcounter`, `\addtocounter`, `\setlength` and `\addtolength`) to allow expression-style input.
Regular mathematical calculations are possible via the `fp` package, which provides infix or RPN notation for calculations. The powerful `pgf` package provides a similar and more extended functionality, as does LaTeX3's `l3fp`.