public static Matrix2x2d PolarDecomposition(Matrix2x2d m)
{
Matrix2x2d q = m + new Matrix2x2d(m.m11, -m.m10, -m.m01, m.m00);
Vector2d c0 = q.GetColumn(0);
Vector2d c1 = q.GetColumn(1);
double s = c0.Magnitude;
q.SetColumn(0, c0 / s);
q.SetColumn(1, c1 / s);
return(q);
}
/// <summary>
/// The Inverse of the matrix copied into mInv.
/// Returns false if the matrix has no inverse.
/// A matrix multipled by its inverse is the idenity.
/// </summary>
public bool TryInverse(ref Matrix2x2d mInv)
{
double det = Determinant;
if (Math.Abs(det) <= 1e-09)
{
return(false);
}
double invDet = 1.0 / det;
mInv.m00 = m11 * invDet;
mInv.m01 = -m01 * invDet;
mInv.m10 = -m10 * invDet;
mInv.m11 = m00 * invDet;
return(true);
}
/// <summary>
/// Are these matrices equal.
/// </summary>
public bool EqualsWithError(Matrix2x2d m, double eps)
{
if (Math.Abs(m00 - m.m00) > eps)
{
return(false);
}
if (Math.Abs(m10 - m.m10) > eps)
{
return(false);
}
if (Math.Abs(m01 - m.m01) > eps)
{
return(false);
}
if (Math.Abs(m11 - m.m11) > eps)
{
return(false);
}
return(true);
}
/// <summary>
/// A matrix copied from the matrix m.
/// </summary>
public Matrix2x2d(Matrix2x2d m)
{
m00 = m.m00; m01 = m.m01;
m10 = m.m10; m11 = m.m11;
}
/// <summary>
/// Are these matrices equal.
/// </summary>
public bool Equals(Matrix2x2d mat)
{
return(this == mat);
}
