Kcalc is a calculator

Calculator

An electronic calculator is a small, portable, usually inexpensive electronic device used to perform the basic operations of arithmetic. Modern calculators are more portable than most computers, though most PDAs are comparable in size to handheld calculators.The first solid-state electronic...

 application integrated with the KDE

KDE

KDE is an international free software community producing an integrated set of cross-platform applications designed to run on Linux, FreeBSD, Microsoft Windows, Solaris and Mac OS X systems...

-Desktop. In the default view it includes a number pad, buttons for adding, subtracting, multiplying, and dividing, brackets, memory keys, percent, reciprocal, factorial, square, square root, and x to the power of y buttons.

Additional buttons for scientific and engineering (trigonometric and logarithmic functions), statistics and logic functions can be enabled as needed. 6 additional buttons can be predefined with mathematical constant

Mathematical constant

A mathematical constant is a special number, usually a real number, that is "significantly interesting in some way". Constants arise in many different areas of mathematics, with constants such as and occurring in such diverse contexts as geometry, number theory and calculus.What it means for a...

s and physical constant

Physical constant

A physical constant is a physical quantity that is generally believed to be both universal in nature and constant in time. It can be contrasted with a mathematical constant, which is a fixed numerical value but does not directly involve any physical measurement.There are many physical constants in...

s or custom values. It is ideal for calculations involving varying bases.

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