private Expression factor(Expression otherExpr) {
if (!otherExpr.hasX2Coefficient() || otherExpr.isZero()) return null;
Fraction x2 = otherExpr.getX2Coefficient();
Fraction x1 = otherExpr.getXCoefficient();
Fraction x0 = otherExpr.getConstant();
Fraction a = expr.getXCoefficient();
Fraction b = expr.getConstant();
Fraction c = x2.divide(a);
Fraction d = x0.divide(b);
if (x1.equals(b.multiply(c).add(a.multiply(d)))) {
return new Expression(c, d);
}
return null;
}
private static int getTimeUnits(Fraction length, int tempo, int unitsInMinute) {
int minute = 60 * unitsInMinute;
int semibreveTime = 4 * minute / tempo;
return length.multiply(semibreveTime).intValue();
}