/// <summary>
/// Calculates the minimum absolute value of all entries of an <see cref="IReducible"/>.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double MinAbsolute(this IReducible reducible)
{
return(reducible.Reduce(double.MaxValue, (x, min) =>
{
double abs = Math.Abs(x);
return abs < min ? abs : min;
},
(nz, min) => 0.0 < min ? 0.0 : min, min => min));
}
/// <summary>
/// Calculates the maximum absolute value of all entries of an <see cref="IReducible"/>.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double MaxAbsolute(this IReducible reducible)
{
return(reducible.Reduce(double.MinValue, (x, max) =>
{
double abs = Math.Abs(x);
return abs > max ? abs : max;
},
(nz, max) => 0.0 > max ? 0.0 : max, max => max));
}
private static object MethodReduce(ITransformer xf, object acc, IReducible obj)
{
return(xf.Result(obj.Reduce(new Func <object, object, object>(xf.Step), acc)));
}
/// <summary>
/// Calculates the sum over all entries of an <see cref="IReducible"/>.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double Sum(this IReducible reducible)
{
return(reducible.Reduce(0.0, (x, sum) => x + sum, (nz, sum) => sum, sum => sum));
}
/// <summary>
/// Calculates the product over all entries of an <see cref="IReducible"/>.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double Product(this IReducible reducible)
{
return(reducible.Reduce(1.0, (x, prod) => x * prod, (nz, prod) => nz > 0 ? 0 : prod, prod => prod));
}
/// <summary>
/// Calculates the Euclidian norm or 2-norm over all entries of an <see cref="IReducible"/>. For more see
/// https://en.wikipedia.org/wiki/Norm_(mathematics)#Euclidean_norm. WARNING: most classes that implement
/// <see cref="IReducible"/> will provide far more efficient methods for calculating norms. Use them instead.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double Norm2(this IReducible reducible)
{
return(reducible.Reduce(0.0, (x, sum) => x + sum, (nz, sum) => sum, sum => Math.Sqrt(sum)));
}
/// <summary>
/// Calculates the minimum value of all entries of an <see cref="IReducible"/>.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double Min(this IReducible reducible)
{
return(reducible.Reduce(double.MaxValue, (x, min) => x < min ? x : min,
(nz, min) => 0.0 < min ? 0.0 : min, min => min));
}
/// <summary>
/// Calculates the maximum value of all entries of an <see cref="IReducible"/>.
/// </summary>
/// <param name="reducible">A matrix, vector or similar collection.</param>
public static double Max(this IReducible reducible)
{
return(reducible.Reduce(double.MinValue, (x, max) => x > max ? x : max,
(nz, max) => 0.0 > max ? 0.0 : max, max => max));
}