Xcalc
Encyclopedia
xcalc is an on-screen calculator
program
for the X Window System
. It can be used in algebraic mode or in reverse polish notation
. Early versions also featured a slide rule
mode, but this was removed for X11R4, which was released in 1989. The sliderule program for the BSD operating systems is based on the slide rule in xcalc.
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...
program
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
for the X Window System
X Window System
The X window system is a computer software system and network protocol that provides a basis for graphical user interfaces and rich input device capability for networked computers...
. It can be used in algebraic mode or in reverse polish notation
Reverse Polish notation
Reverse Polish notation is a mathematical notation wherein every operator follows all of its operands, in contrast to Polish notation, which puts the operator in the prefix position. It is also known as Postfix notation and is parenthesis-free as long as operator arities are fixed...
. Early versions also featured a slide rule
Slide rule
The slide rule, also known colloquially as a slipstick, is a mechanical analog computer. The slide rule is used primarily for multiplication and division, and also for functions such as roots, logarithms and trigonometry, but is not normally used for addition or subtraction.Slide rules come in a...
mode, but this was removed for X11R4, which was released in 1989. The sliderule program for the BSD operating systems is based on the slide rule in xcalc.