public function concat(Converter $converter)
{
if ($converter instanceof self) {
$offset = $this->offset + $converter->getOffset();
return $offset == 0.0 ? Converter::IDENTITY() : new self($offset);
}
return parent::concat($converter);
}
public function concat(Converter $converter)
{
if ($converter instanceof self) {
$factor = $this->factor * $converter->getFactor();
return $factor == 1.0 ? Converter::IDENTITY() : new self($factor);
}
return parent::concat($converter);
}
public function concat(Converter $converter)
{
if (!$converter instanceof self) {
return parent::concat($converter);
}
$dividend = $this->dividend * $converter->getDividend();
$divisor = $this->divisor * $converter->getDivisor();
$gcd = $this->gcd($dividend, $divisor);
$dividend = $dividend / $gcd;
$divisor = $divisor / $gcd;
if ($dividend == 1 && $divisor == 1) {
return Converter::IDENTITY();
}
return new self($dividend, $divisor);
}
public function getConverterTo(Unit $that)
{
if ($this->equals($that)) {
return Converter::IDENTITY();
}
$thisSystemUnit = $this->getStandardUnit();
$thatSystemUnit = $that->getStandardUnit();
if ($thisSystemUnit->equals($thatSystemUnit)) {
return $that->toStandardUnit()->inverse()->concat($this->toStandardUnit());
}
if (!$thisSystemUnit->getDimension()->equals($thatSystemUnit->getDimension())) {
throw new \RuntimeException(sprintf('Dimension %s is not compatible with dimension %s.', $thisSystemUnit->getDimension()->getSymbol(), $thatSystemUnit->getDimension()->getSymbol()));
}
$thisTransform = $this->toStandardUnit()->concat($thisSystemUnit->toBaseUnits());
$thatTransform = $that->toStandardUnit()->concat($thatSystemUnit->toBaseUnits());
return $thatTransform->inverse()->concat($thisTransform);
}
public function toBaseUnits()
{
$result = Converter::IDENTITY();
foreach ($this->elements as $element) {
$unit = $element->unit;
$converter = $unit->toBaseUnits();
if (!$converter->isLinear()) {
throw new \RuntimeException($unit->getSymbol() . ' is non-linear.');
}
if ($element->root != 1) {
throw new \RuntimeException($unit->getSymbol() . ' holds a base unit with fractional exponent');
}
$pow = $element->pow;
if ($pow < 0) {
$pow = -$pow;
$converter = $converter->inverse();
}
for ($j = 0; $j < $pow; ++$j) {
$result = $result->concat($converter);
}
}
return $result;
}
public function toBaseUnits()
{
return Converter::IDENTITY();
}
public function toStandardUnit()
{
return Converter::IDENTITY();
}