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An extensible, advanced desk calculatorand mathematical tool written in Emacs Lisp by DaveGillespie . Calc runs as part of GNUEmacs. You can use Calc as only a simple four-functioncalculator, but it also provides additional features includingchoice of algebraic or RPN (stack-based) entry,logarithms, trigonometric and financial functions, arbitraryprecision, complex numbers, vectors, matrices, dates, times,infinities, sets, algebraic simplification, differentiation,and integration.Latest version: 2.02, as of 1994-11-08.FTP calc-2.02.tar.z from your nearest GNU archive site.