/// <summary>
/// Multiply two fractions
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns>The product of a and b</returns>
public static FractionModel Multiply(FractionModel a, FractionModel b)
{
var res = new FractionModel(a.Numerator * b.Numerator, a.Denominator * b.Denominator);
res.Simplify();
return(res);
}
/// <summary>
/// Reduce a fraction
/// </summary>
/// <param name="m">The fraction to reduce</param>
public static void Simplify(this FractionModel m)
{
int gcd = FindGreatestCommonFactor(m);
m.Numerator /= gcd;
m.Denominator /= gcd;
//return new FractionModel(m.Numerator / gcd, m.Denominator / gcd);
}
/// <summary>
/// Subtracts two fractions
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns>The difference of a and f=b</returns>
public static FractionModel Subtract(FractionModel a, FractionModel b)
{
int lcm = FindLeastCommonMultiple(a.Denominator, b.Denominator);
int num = a.Numerator * (lcm / a.Denominator) - b.Numerator * (lcm / b.Denominator);
FractionModel res = new FractionModel(num, lcm);
res.Simplify();
return(res);
}
/// <summary>
/// Convert a decimal to a fraction
/// </summary>
/// <param name="d">The decimal to convert</param>
/// <returns>The decimal represented as a fraction</returns>
public static FractionModel ConvertDecimalToFraction(decimal d)
{
double decimalPlaces = NumberOfDecimalPlaces(d);
int multiplier = (int)Math.Pow(10, decimalPlaces);
FractionModel fraction = new FractionModel((int)(d * multiplier), multiplier);
fraction.Simplify();
return(fraction);
}
/// <summary>
/// Divides two fractions
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns>The quotient of a and b</returns>
public static FractionModel Divide(FractionModel a, FractionModel b)
{
var res = Multiply(a, GetReciprocal(b));
res.Simplify();
if (res.Denominator < 0 && res.Numerator < 0)
{
res.Numerator = Math.Abs(res.Numerator);
res.Denominator = Math.Abs(res.Denominator);
}
return(res);
}
/// <summary>
/// Try to parse a fraction
/// </summary>
/// <param name="value">The value to parse</param>
/// <param name="fraction">The result of parsing value, or 0 on failure</param>
/// <returns>True on success, false on failure</returns>
public static bool TryParseFraction(string value, out FractionModel fraction)
{
fraction = new FractionModel(0, 1);
try
{
fraction = ParseFraction(value);
}
catch (ArgumentException)
{
return(false);
}
return(true);
}
/// <summary>
/// Finds the greatest common divisor of a fraction
/// </summary>
/// <param name="model">The fraction model to find the GCD of</param>
/// <returns>The greatest common divisor</returns>
public static int FindGreatestCommonFactor(FractionModel model)
{
return(FindGreatestCommonFactor(model.Denominator, model.Numerator));
}
/// <summary>
/// Return the number of places after the decimal point
/// </summary>
/// <param name="model">The FractionModel to check</param>
/// <returns>The number of places after the decimal point</returns>
public static int NumberOfDecimalPlaces(FractionModel model)
{
decimal number = decimal.Divide(model.Numerator, model.Denominator);
return(NumberOfDecimalPlaces(number));
}
/// <summary>
/// Get the Reciprocal of a fraction
/// </summary>
/// <param name="model">The fraction to get the Reciprocal of</param>
/// <returns>The reciprocal of the fraction</returns>
public static FractionModel GetReciprocal(FractionModel model)
{
return(new FractionModel(model.Denominator, model.Numerator));
}
