Calc-50

Calc-50 is a high-precision scientific graphing RPN calculator. It carries over 50 digits of accuracy and has a large number of mathematical functions, including trig and hyperbolic functions and their inverses, and math special functions such as gamma, beta, psi, exponential integral, sine, cosine, and log integrals, Bessel functions, and more. It is programmable, with functions that take user functions and find derivatives, integrals, function max/min, and roots. Calc-50 also provides complex arithmetic and elementary functions.