calculator - simple desktop calculator calculator

The FOX Calculator is a simple desktop calculator geared toward the programmer. It supports not only a full complement scientific functions, but also common operations that programmers need, such as bitwise operations, bitwise shifting, and base-2 logarithm and exponents, and numeric conversion between hexadecimal, octal, binary, and decimal. The FOX Calculator implements correct operator precedences, so expressions like 2+3*5 yield the correct result, which is 17, and not 25. Also featured is a constant memory, which permanently stores its value even if you exit the calculator and restart it later.

Pressing on the calculator icon brings up the Calculator Preferences dialog. The Calculator Preferences dialog comprises three settings: - Settings for the calculator itself;

- Color settings of the button groups;

- Information about the calculator. In the Calculator settings panel, you can change font used for the display, by pressing the "Set..." button to bring up the standard Font Selection Dialog. You can change the way numbers are printed as well. Checking "Always show exponent" will cause the calculator display always to display the number in exponential notation. Checking "Never show exponent" will cause the calculator to render the number in simple dot notation. The precision can be set by means of the spin button; the default precision is set to 16. Finally, the calculator can be set to beep when errors occur. In the Color settings panel, you can change the colors of the various button groups. The buttons are grouped by function; the numbers are in one group, and the operators are in another, and so on. In the About panel, some information is presented about the calculator, like version number and author's contact.

You can enter a number by clicking on the digit buttons, or simply hit the right digit on the keyboard. Numbers in exponential notation are entered by entering the mantissa first, then hitting the "EXP" button, and then entering the exponent. Up to 3 digits may be entered for the exponent; entering more than 3 will cause the digits to shift, i.e. the first digit entered will be dropped and replaced by the second, the second digit will be replaced by the third, and the third will be replaced by the new input. Changing the sign of the exponent is accomplished by hittin the \"+/-\" button. At any time, you can hit the Backspace key to delete the last digit entered. Two numbers, pi and e (euler's number) may be entered with a single button:

pi - Enters the number 3.1415926535897932384626433833

e - Enters the number 2.7182818284590452353602874713 (hit the "inv" button first)

The operators in the FOX Calculator are the usual suspects:

+ Addition

- Substraction

* Multiplication

/ Floating point division

In addition, FOX Calculator also includes bitwise operators, such as:

AND Bit-wise logical and

OR Bit-wise logical or

XOR Bit-wise logical exclusive or

NOT Bit-wise logical not

SHL Bit-wise shift left

SHR Bit-wise shift right

SAR Bit-wise signed shift right (hit the "inv" button first)

Also nice for programmers is the inclusion of integer operations:

mod Integer modulo

div Integer division (hit the \"inv\" button first)

All the operators have certain precedence relations with each other, so that an expression is evaluated correctly.

The Calculator incorporates the usual trigonometric functions:

sin Sine

cos Cosine

tan Tangent

asin Inverse sine or arc sine (hit the "inv" button first)

acos Inverse cosine

atan Inverse tangent

sinh Hyperbolic sine (hit the "hyp" button first)

cosh Hyperbolic cosine

tanh Hyperbolic tangent

asinh Inverse hyperbolic sine (hit the "hyp" and "inv"buttons first)

acosh Inverse hyperbolic cosine

atanh Inverse hyperbolic tangent

For the first 6 functions, the angle mode determines whether the argument is specified in terms of degrees, radians, or grad. Note that the angle mode is preserved across invocations of the Calculator.

Other functions supported by the calculator are the following:

log Base 10 logarithm

ln Natural logarithm

2log Base 2 logarithm

x! Factorial

nPr Permutations

nCr Combinations

sqrt Square root

x^y X raised to the power y

1/x Reciprocal

10^x Base 10 exponentiation (hit the "inv" button first)

e^x Exponentiation

2^x Base 2 exponentiation

x^1/y X raised to the power 1/y

x^2 X squared

The calculator works in IEEE 746 double precision mode; for bit-wise operations, it uses 32 bit integers. Thus, the numeric limits are as follows:

Smallest real number: 2.2250738585072010e-308

Largest real number: 1.7976931348623158e+308

Smallest integer number: 0

Largest integer number: 4294967295

This manpage was originally written by Bastian Kleineidam <calvin@debian.org> for the Debian distribution of the FOX Toolkit. The main author of FOX is Jeroen van der Zijp <jeroen@fox-toolkit.org>. For a list of contributors see /usr/share/doc/libfox0.99/AUTHORS.