BigDecimal
Arithmetic and calculus with decimal numbers of arbitrary precision.
...In BigDecimal all the arithmetic operations are implemented, including, logarithms, systems resolution of linear equations, trigonometric functions, polynomial regression, hyperbolic functions, the notorious gamma function (factorial for non-integer real numbers) and more that will be implemented still.
My intention is, at a minimum, to implement all the mathematical functions of the Windows calculator, and at most, if any, all the mathematical functions of Office Excel.