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# bcdiv

(PHP 4, PHP 5)

bcdivDivide two arbitrary precision numbers

### Description

string bcdiv ( string `\$left_operand` = "" , string `\$right_operand` = "" [, int `\$scale` = int ] )

Divides the `left_operand` by the `right_operand`.

### Parameters

`left_operand`

The left operand, as a string.

`right_operand`

The right operand, as a string.

``` scale```

This optional parameter is used to set the number of digits after the decimal place in the result. You can also set the global default scale for all functions by using bcscale().

### Return Values

Returns the result of the division as a string, or `NULL` if `right_operand` is 0.

### Examples

Example #1 bcdiv() example

``` <?phpecho bcdiv('105', '6.55957', 3);  // 16.007?> ```

• bcmul() - Multiply two arbitrary precision numbers

### User Contributed Notes 4 notes

MM
6 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; ```
Anonymous
3 years ago
``` The custom bcdiv function listed at the top of this page produces very different results from bcdiv, as it rounds instead of truncating the result. Consider the following:<?phpfunction bcdiv_cust( \$first, \$second, \$scale = 0 ){    \$res = \$first / \$second;    return round( \$res, \$scale );}echo bcdiv('1','2','0') . " vs. " bcdiv_cust('1','2','0');  // prints '0 vs. 1'?> ```
Gautam
7 years ago
``` <?php //converting in to required precision of decimal points\$result= bcdiv(89.99999999997,2.57865741235478,2); echo "\$result";  // 34.90 result with 2 decimal points?> ```
-1
cristianDOTzuddas]NOSPAM[gmailDOTcom
9 years ago
``` Decimal to binary conversion, using BC Math.Note: this function is VERY slow if the decimal number is too big!<?function bc_decbin(\$dec_str) {    if (strlen(\$dec_str)>0) {        \$bin_str = '';        do {            if (((int)\$dec_str[strlen(\$dec_str)-1] % 2) === 0)                \$bin_str .= '0';            else                \$bin_str .= '1';                        \$dec_str = bcdiv(\$dec_str, '2');        } while (\$dec_str!='0');                return strrev(\$bin_str);    }    else        return null;}?>-----Cristianwww.CodeFlower.com ```