(PHP 4, PHP 5, PHP 7, PHP 8)
bcscale — Set or get default scale parameter for all bc math functions
Sets the default scale parameter for all subsequent calls to bc math functions that do not explicitly specify a scale parameter.
Gets the current scale factor.
scaleThe scale factor.
Returns the old scale when used as setter. Otherwise the current scale is returned.
This function throws a ValueError if scale
is outside the valid range.
| Version | Description |
|---|---|
| 8.0.0 |
scale is now nullable.
|
| 7.3.0 |
bcscale() can now be used to get the current scale
factor; when used as setter, it now returns the old scale value.
Formerly, scale was mandatory, and
bcscale() always returned true .
|
Example #1 bcscale() example
<?php
// default scale : 3
bcscale(3);
echo bcdiv('105', '6.55957'); // 16.007
// this is the same without bcscale()
echo bcdiv('105', '6.55957', 3); // 16.007
?>These functions DO NOT round off your values. No arbitrary precision libraries do it this way. It stops calculating after reaching scale of decimal places, which mean that your value is cut off after scale number of digits, not rounded. To do the rounding use something like this:
<?php
function bcround($number, $scale=0) {
$fix = "5";
for ($i=0;$i<$scale;$i++) $fix="0$fix";
$number = bcadd($number, "0.$fix", $scale+1);
return bcdiv($number, "1.0", $scale);
}
?>Executing bcsacle() will change the scale value of fpm.conf, not only the current process.Simple, easy way to remove excess trailing zeros using rtrim:
<php>
// $total is the result of a bcmath calculation
if ( strpos($total, '.') !== false ):
$total = rtrim($total, '0');
$total = rtrim($total, '.');
endif;
</php>edited bcround function with negative number support:
<?php
function bcround($number, $scale=0) {
if($scale < 0) $scale = 0;
$sign = '';
if(bccomp('0', $number, 64) == 1) $sign = '-';
$increment = $sign . '0.' . str_repeat('0', $scale) . '5';
$number = bcadd($number, $increment, $scale+1);
return bcadd($number, '0', $scale);
}
?>