# PHP – How to get the modulus of an arbitrary precision number using bcmod() function?

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In PHP, bcmod() math function is used to calculate the modulus of an arbitrary precision number. The bcmod() function takes an arbitrary precision number as strings and it gives the result as a modulus of numbers after scaling the result to an identified precision. Or, we can say that it gets the remainder after dividing string_num1 by string_num2. Unless the string_num2 is 0, the result has the same sign as string_num1.

## Syntax

bcmod(string_$num1, string_$num2, [, int $scale=0]) Or, bcmod(string$dividend, string $divisor[, int$scale=0])

Note− The above syntax will get the remainder of dividing $string_num1 by$string_num2. Unless string_num2 is 0, the result has the same sign as string_num1.

## Parameters

The bcmod() function accepts two different parameters, $dividend and$modulus.

• $dividend− It represents the dividend that is divided by the given modulus value$modulus and it is the string type parameter.

• $modulus− It is the string type parameter and it is used to represent the modulus. ## Return Value The bcmod() function returns the remainder when the dividend is divided by the modulus. If the modulus is 0, then the function returns null. ## Example1 - bcmod() PHP function without using the scale parameter. <?php // input numbers with arbitrary precision$dividend = "25.666";
$modulus = "7"; // calculates the modulus$result = bcmod($dividend,$modulus);
echo "Output without using scale value: ", $result; ?> ## Output Output without using scale value: 4 ## Example 2 - bcmod() PHP function using the scale parameter Now, we will take the same input values with a scale value of 4 and check the output. <?php // input numbers with arbitrary precision$dividend = "25.666";
$modulus = "7"; //using scale value 4$scaleVal =4;

// calculates the modulus
$result = bcmod($dividend, $modulus,$scaleVal);
echo "Output with scale value: ", \$result;
?>

## Output

Output with scale value: 4.6660

## Example 3

<?php
bcscale(1);

// 0.5 as of PHP 7.2.0; 0 previously
echo bcmod('5.7', '1.3');
?>

## Output

0.5

Note− The scale parameter was added from PHP 7.2.0 version.