What is the purpose of bcsub function in PHP?

The bcsub function in PHP is used to perform subtraction operations on two arbitrary precision numbers. It is one of the mathematical functions used for handling high-precision calculations.

The syntax of the bcsub function is:
string bcsub(string $left_operand, string $right_operand [, int $scale = 0])

$left_operand and $right_operand are the two operands to be subtracted, which can be any long numeric strings. The $scale parameter is optional and specifies the number of decimal places in the result, with a default of 0.

The bcsub function returns a string representing the result.

Here is an example of using the bcsub function:

$num1 is equal to 1234.56 and $num2 is equal to 789.01.

Calculate the difference between $num1 and $num2 and store the result in $result.

output the result: 445.55

In the example above, the bcsub function subtracts $num2 from $num1, resulting in 445.55. Since the $scale parameter is not specified, the result will be truncated to the integer part.