@Override
public AMExpression simplifyInOneStep() {
AMExpression f1 = factor1.simplifyInOneStep();
AMExpression f2 = factor2.simplifyInOneStep();
if (f1 instanceof BasicNumber) {
if (f2 instanceof BasicNumber)
return ((BasicNumber) f1).multiply((BasicNumber) f2); // n.n' -> n*n'
if (((BasicNumber) f1).isZero()) return new BasicNumber(0); // 0.a -> 0
if (((BasicNumber) f1).equals(new BasicNumber(1))) return f2; // 1.a -> a
if (((BasicNumber) f1).isNegative())
return new AdditiveInverse(
new Product(((BasicNumber) f1).negate(), f2)); // (-n).a -> -(n.a)
}
if (f2 instanceof BasicNumber) {
if (((BasicNumber) f2).isZero()) return new BasicNumber(0); // a.0 -> 0
if (((BasicNumber) f2).equals(new BasicNumber(1))) return f1; // a.1 -> a
if (((BasicNumber) f2).isNegative())
return new AdditiveInverse(
new Product(((BasicNumber) f2).negate(), f1)); // a.(-n) -> -(n.a)
}
if (f1 instanceof AdditiveInverse) {
if (f2 instanceof AdditiveInverse)
return new Product(
((AdditiveInverse) f1).getExpr(), ((AdditiveInverse) f2).getExpr()); // (-a).(-b) -> a.b
return new AdditiveInverse(
new Product(((AdditiveInverse) f1).getExpr(), f2)); // (-a).b -> -(a.b)
}
if (f2 instanceof AdditiveInverse)
return new AdditiveInverse(
new Product(((AdditiveInverse) f2).getExpr(), f1)); // a.(-b) -> -(a.b)))
if (f1 instanceof Fraction) {
AMExpression numerator = ((Fraction) f1).getNumerator();
AMExpression denominator = ((Fraction) f1).getDenominator();
if (numerator.equals(new BasicNumber(1)) && denominator.equals(f2))
return new BasicNumber(1); // a.(1/a) -> 1
}
if (f2 instanceof Fraction) {
AMExpression numerator = ((Fraction) f2).getNumerator();
AMExpression denominator = ((Fraction) f2).getDenominator();
if (numerator.equals(new BasicNumber(1)) && denominator.equals(f1))
return new BasicNumber(1); // (1/a).a -> 1
}
return new Product(f1, f2);
}
@Override
public boolean equals(Object expr) {
if (!(expr instanceof Product)) return false;
Product prod = (Product) expr;
return (factor1.equals(prod.getFactor1()) && factor2.equals(prod.getFactor2()));
}
