/// <summary>
/// Returns the one-norm of vector <i>x</i>, which is <i>Sum(abs(x[i]))</i>.
/// </summary>
/// <param name="x">
/// The vector x.
/// </param>
/// <returns>
/// The one-norm of x.
/// </returns>
public static double Norm1(DoubleMatrix1D x)
{
if (x.Size == 0)
{
return(0);
}
return(x.Aggregate(BinaryFunctions.Plus, Math.Abs));
}
/// <summary>
/// Returns the infinity norm of vector <i>x</i>, which is <i>Max(abs(x[i]))</i>.
/// </summary>
/// <param name="x">The vector x.</param>
/// <returns>The infinity norm of matrix <i>A</i></returns>
public static double NormInfinity(DoubleMatrix1D x)
{
// fix for bug reported by [email protected]
if (x.Size == 0)
{
return(0);
}
return(x.Aggregate(Math.Max, Math.Abs));
// if (x.Size==0) return 0;
// return x.aggregate(cern.Cern.Jet.math.Functions.plus,cern.Cern.Jet.math.Functions.abs);
// double max = 0;
// for (int i = x.Size; --i >= 0; ) {
// max = System.Math.Max(max, x.getQuick(i));
// }
// return max;
}
public double Dasum(DoubleMatrix1D x)
{
return(x.Aggregate(F2.Plus, F1.Abs));
}