private vector CountV(vector b, int firstToCount)
{
var e = vector.IdentityVector(firstToCount, b.Length);
var v = new vector(Enumerable.Repeat(0.0, firstToCount).ToList());
b.Elements = b.Skip(firstToCount).ToList();
v.Elements.AddRange(b);
return(v + e * Sign(b[0]) * b.Rate2());
}
private Matrix GetHouseholderMatrix(vector v)
{
var E = Matrix.IdentityMatrix(v.Length);
return(E + (v.Transpose() * v * (-2.0 / vector.ScalarMultiply(v, v))));
}