/** Simplify (x^a)^b when a and b are both numeric.
* @param Node $leftOperand
* @param Node $rightOperand
* @retval Node|null
*/
private function doubleExponentiation($leftOperand, $rightOperand)
{
// (x^a)^b -> x^(ab) for a, b numbers
if ($leftOperand instanceof ExpressionNode && $leftOperand->getOperator() == '^') {
$factory = new MultiplicationNodeFactory();
$power = $factory->makeNode($leftOperand->getRight(), $rightOperand);
$base = $leftOperand->getLeft();
return self::makeNode($base, $power);
}
// No simplification found
return null;
}
/**
* Create a multiplication node representing '$leftOperand * $rightOperand'.
*
* @param mixed $leftOperand
* @param mixed $rightOperand
* @retval ExpressionNode
*
*/
public function multiplication($leftOperand, $rightOperand)
{
return $this->multiplicationFactory->makeNode($leftOperand, $rightOperand);
}