GNU Emacs Calculator  Thomas Klemm  01132009
GNU Emacs Calc Manual
Quote:
Calc is an advanced calculator and mathematical tool that runs as part of the GNU Emacs environment. Very roughly based on the HP28/48 series of calculators, its many features include:
 Choice of algebraic or RPN (stackbased) entry of calculations.
 Arbitrary precision integers and floatingpoint numbers.
 Arithmetic on rational numbers, complex numbers (rectangular and polar), error forms with standard deviations, open and closed intervals, vectors and matrices, dates and times, infinities, sets, quantities with units, and algebraic formulas.
 Mathematical operations such as logarithms and trigonometric functions.
 Programmer's features (bitwise operations, nondecimal numbers).
 Financial functions such as future value and internal rate of return.
 Number theoretical features such as prime factorization and arithmetic modulo M for any M.
 Algebraic manipulation features, including symbolic calculus.
 Moving data to and from regular editing buffers.
 "Embedded mode" for manipulating Calc formulas and data directly inside any editing buffer.
 Graphics using GNUPLOT, a versatile (and free) plotting program.
 Easy programming using keyboard macros, algebraic formulas, algebraic rewrite rules, or extended Emacs Lisp.
Though I'm a frequent user of xemacs I was not aware of this powerful calculator.
It can be started with: M# c
