IV. BCMath Arbitrary Precision Mathematics Functions

Introduktion

For arbitrary precision mathematics PHP offers the Binary Calculator which supports numbers of any size and precision, represented as strings.

Systemkrav

Since PHP 4.0.4, libbcmath is bundled with PHP. You don't need any external libraries for this extension.

Installation

In PHP 4, these functions are only available if PHP was configured with --enable-bcmath. In PHP 3, these functions are only available if PHP was NOT configured with --disable-bcmath.

Windows versionen af PHP har indbygget support for denne udvidelse. Du behøver ikke indsætte ekstra udvidelser for at bruge disse funktioner.

Runtime Konfiguration

Virkemåden af disse funktioner er berørt af indstillinger i php.ini.

Tabel 1. BC math configuration options

Name	Default	Changeable
bcmath.scale	0	PHP_INI_ALL

For further details and definition of the PHP_INI_* constants see ini_set().

Her er en kort forklaring på konfigurations-direktiverne.

bcmath.scale integer: Number of decimal digits for all bcmath functions. See also bcscale().

Ressourcetyper

Denne udvidelse har ingen ressourcetyper defineret.

Foruddefinerede Konstanter

Denne udvidelse har ingen konstanter.

Indholdsfortegnelse
bcadd -- Add two arbitrary precision numbers
bccomp -- Compare two arbitrary precision numbers
bcdiv -- Divide two arbitrary precision numbers
bcmod -- Get modulus of an arbitrary precision number
bcmul -- Multiply two arbitrary precision number
bcpow -- Raise an arbitrary precision number to another
bcpowmod -- Raise an arbitrary precision number to another, reduced by a specified modulus.
bcscale -- Set default scale parameter for all bc math functions
bcsqrt -- Get the square root of an arbitrary precision number
bcsub -- Subtract one arbitrary precision number from another