public Rational abs() {
Rational result = new Rational(1, 1);
if ((this.numerator() >= 0 && this.denominator() >= 0)
|| (this.numerator() < 0 && this.denominator() < 0)) {
result._numerator = this.numerator();
result._denominator = this.denominator();
} else {
result._numerator = -this.numerator();
result._denominator = this.denominator();
}
return result;
}
