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BCMath Arbitrary Precision Mathematics Functions


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


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


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.

BC math configuration options
Name Default Changeable Changelog
bcmath.scale "0" PHP_INI_ALL  
For flere detaljer og definationer af PHP_INI_* constanterne, se ini_set() dokumentation.

Her er en kort forklaring på konfigurations-direktiverne.

bcmath.scale integer

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


Denne udvidelse har ingen ressourcetyper defineret.

Foruddefinerede Konstanter

Denne udvidelse har ingen konstanter.

Table of Contents

  • 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