KCalc

KCalc is a scientific software calculator integrated with the KDE Gear.

[2] KCalc includes trigonometric functions, logic operations, saved previous results, copy and paste, a configure UI, and statistical computations.

The history function uses a stack method.

[3][4] KCalc also supports boolean operations.

[3] Since version 2 (included in KDE 3.5) KCalc offers arbitrary precision.