bcdiv

(PHP 4, PHP 5, PHP 7, PHP 8)

bcdiv — Divide two arbitrary precision numbers

Опис

bcdiv(string $num1, string $num2, ?int $scale = null): string

Divides num1 by num2.

Параметри

num1: The dividend, as a string.
num2: The divisor, as a string.
scale: This parameter is used to set the number of digits after the decimal place in the result. If null, it will default to the default scale set with bcscale(), or fallback to the value of the bcmath.scale INI directive.

Значення, що повертаються

Returns the result of the division as a string.

Помилки/виключення

This function throws a ValueError in the following cases:

num1 or num2 is not a well-formed BCMath numeric string.
scale is outside the valid range.

This function throws a DivisionByZeroError exception if num2 is 0.

Журнал змін

Версія	Опис
8.0.0	`scale` is now nullable.
8.0.0	Dividing by `0` now throws a DivisionByZeroError exception instead of returning `null`.

Приклади

Приклад #1 bcdiv() example

<?php

echo bcdiv('105', '6.55957', 3);  // 16.007

?>

Прогляньте також

bcdivmod() - Get the quotient and modulus of an arbitrary precision number
bcmod() - Get modulus of an arbitrary precision number
bcmul() - Multiply two arbitrary precision numbers
BcMath\Number::div()

Found A Problem?

Learn How To Improve This Page • Submit a Pull Request • Report a Bug

＋add a note

User Contributed Notes 1 note

down

MM ¶

17 years ago

Perhaps some one can find useful this function to compute the modular inverse of a integer (extended euclidean algorithm):

  function invmod($a,$b) {
    $n=$b;
    $x=0; $lx=1; $y=1; $ly=0;
    while ($b) {
      $t=$b;
      $q=bcdiv($a,$b,0);
      $b=bcmod($a,$b);
      $a=$t;
      $t=$x; $x=bcsub($lx,bcmod(bcmul($q,$x),$n)); $lx=$t;
      $t=$y; $y=bcsub($ly,bcmod(bcmul($q,$y),$n)); $ly=$t;
    }
    if (bccomp($lx,0) == -1)
      $lx=bcadd($lx,$n);
    return $lx;
  }

  // verify

  $n="2447995268898324993537772139997802321";
  $t="64941057316178801556773346239351236811";
  $m="123456789";
  $i=invmod($t,$n);
  // (t*m)*inv(t) is m
  echo bcmod(bcmul(bcmod(bcmul($t,$m),$n),$i),$n) == $m;

＋add a note