How to round/ceil/floor a bcmath number in PHP?

echo ceil(31497230840470473074370324734723042.6);

// Expected result
31497230840470473074370324734723043

// Prints
<garbage>

$x = '31497230840470473074370324734723042.9';

bcscale(100);
var_dump(bcFloor($x));
var_dump(bcCeil($x));
var_dump(bcRound($x));

function bcFloor($x)
{
    $result = bcmul($x, '1', 0);
    if ((bccomp($result, '0', 0) == -1) && bccomp($x, $result, 1))
    	$result = bcsub($result, 1, 0);

    return $result;
}

function bcCeil($x)
{
    $floor = bcFloor($x);
    return bcadd($floor, ceil(bcsub($x, $floor)), 0);
}

function bcRound($x)
{
    $floor = bcFloor($x);
    return bcadd($floor, round(bcsub($x, $floor)), 0);
}

function bcceil($number)
{
    if ($number[0] != '-')
    {
        return bcadd($number, 1, 0);
    }

    return bcsub($number, 0, 0);
}

function bcfloor($number)
{
    if ($number[0] != '-')
    {
        return bcadd($number, 0, 0);
    }

    return bcsub($number, 1, 0);
}

function bcround($number, $precision = 0)
{
    if ($number[0] != '-')
    {
        return bcadd($number, '0.' . str_repeat('0', $precision) . '5', $precision);
    }

    return bcsub($number, '0.' . str_repeat('0', $precision) . '5', $precision);
}

assert(bcceil('4.3') == ceil('4.3')); // true
assert(bcceil('9.999') == ceil('9.999')); // true
assert(bcceil('-3.14') == ceil('-3.14')); // true

assert(bcfloor('4.3') == floor('4.3')); // true
assert(bcfloor('9.999') == floor('9.999')); // true
assert(bcfloor('-3.14') == floor('-3.14')); // true

assert(bcround('3.4', 0) == number_format('3.4', 0)); // true
assert(bcround('3.5', 0) == number_format('3.5', 0)); // true
assert(bcround('3.6', 0) == number_format('3.6', 0)); // true
assert(bcround('1.95583', 2) == number_format('1.95583', 2)); // true
assert(bcround('5.045', 2) == number_format('5.045', 2)); // true
assert(bcround('5.055', 2) == number_format('5.055', 2)); // true
assert(bcround('9.999', 2) == number_format('9.999', 2)); // true