Exemplo n.º 1
0
        EigenvalueDecomposition(
            double[] d,
            double[] e)
        {
            /* TODO: unit test missing for EigenvalueDecomposition constructor. */

            _n = d.Length;
            _v = Matrix.CreateMatrixData(_n, _n);

            _d = new double[_n];
            Array.Copy(d, 0, _d, 0, _n);

            _e = new double[_n];
            Array.Copy(e, 0, _e, 1, _n - 1);

            for (int i = 0; i < _n; i++)
            {
                _v[i][i] = 1;
            }

            SymmetricDiagonalize();

            _eigenValuesReal = new Vector(_d);
            _eigenValuesImag = new Vector(_e);
            _eigenValues     = ComplexVector.Create(_d, _e);

            InitOnDemandComputations();
        }
Exemplo n.º 2
0
        ComputeOrthogonalFactor()
        {
            double[][] Q = Matrix.CreateMatrixData(m, Math.Min(m, n));
            for (int k = Math.Min(m, n) - 1; k >= 0; k--)
            {
                Q[k][k] = 1.0;
                for (int j = k; j < Math.Min(m, n); j++)
                {
                    if (QR[k][k] == 0.0)
                    {
                        continue;
                    }

                    double s = 0.0;
                    for (int i = k; i < m; i++)
                    {
                        s += QR[i][k] * Q[i][j];
                    }

                    s = (-s) / QR[k][k];
                    for (int i = k; i < m; i++)
                    {
                        Q[i][j] += s * QR[i][k];
                    }
                }

                double columnSign = Math.Sign(Rdiag[k]);
                for (int i = 0; i < m; i++)
                {
                    Q[i][k] *= columnSign;
                }
            }

            return(new Matrix(Q));
        }
        ComputeOrthogonalFactor()
        {
            double[][] q = Matrix.CreateMatrixData(M, Math.Min(M, N));
            for (int k = Math.Min(M, N) - 1; k >= 0; k--)
            {
                q[k][k] = 1.0;
                for (int j = k; j < Math.Min(M, N); j++)
                {
                    if (_qr[k][k] == 0.0)
                    {
                        continue;
                    }

                    double s = 0.0;
                    for (int i = k; i < M; i++)
                    {
                        s += _qr[i][k] * q[i][j];
                    }

                    s = (-s) / _qr[k][k];
                    for (int i = k; i < M; i++)
                    {
                        q[i][j] += s * _qr[i][k];
                    }
                }

                double columnSign = Math.Sign(_rDiag[k]);
                for (int i = 0; i < M; i++)
                {
                    q[i][k] *= columnSign;
                }
            }

            return(new Matrix(q));
        }
Exemplo n.º 4
0
 ComputeOrthogonalFactor()
 {
     double[][] Q = Matrix.CreateMatrixData(m, n);
     for (int k = n - 1; k >= 0; k--)
     {
         for (int i = 0; i < m; i++)
         {
             Q[i][k] = 0.0;
         }
         Q[k][k] = 1.0;
         for (int j = k; j < n; j++)
         {
             if (QR[k][k] != 0)
             {
                 double s = 0.0;
                 for (int i = k; i < m; i++)
                 {
                     s += QR[i][k] * Q[i][j];
                 }
                 s = (-s) / QR[k][k];
                 for (int i = k; i < m; i++)
                 {
                     Q[i][j] += s * QR[i][k];
                 }
             }
         }
     }
     return(new Matrix(Q));
 }
Exemplo n.º 5
0
        ComputeUpperTriangularFactor()
        {
            double[][] R = Matrix.CreateMatrixData(Math.Min(n, m), n);
            for (int i = 0; i < Math.Min(n, m); i++)
            {
                double   rowSign = Math.Sign(Rdiag[i]);
                double[] Ri      = R[i];
                for (int j = 0; j < Ri.Length; j++)
                {
                    if (i < j)
                    {
                        Ri[j] = rowSign * QR[i][j];
                    }
                    else if (i == j)
                    {
                        Ri[j] = rowSign * Rdiag[i];
                    }
                    else
                    {
                        Ri[j] = 0.0;
                    }
                }
            }

            return(new Matrix(R));
        }
        ComputeUpperTriangularFactor()
        {
            double[][] r = Matrix.CreateMatrixData(Math.Min(N, M), N);
            for (int i = 0; i < Math.Min(N, M); i++)
            {
                double   rowSign = Math.Sign(_rDiag[i]);
                double[] ri      = r[i];
                for (int j = 0; j < ri.Length; j++)
                {
                    if (i < j)
                    {
                        ri[j] = rowSign * _qr[i][j];
                    }
                    else if (i == j)
                    {
                        ri[j] = rowSign * _rDiag[i];
                    }
                    else
                    {
                        ri[j] = 0.0;
                    }
                }
            }

            return(new Matrix(r));
        }
Exemplo n.º 7
0
        EigenvalueDecomposition(
            double[] d,
            double[] e
            )
        {
            // TODO: unit test missing for EigenvalueDecomposition constructor.

            n = d.Length;
            V = Matrix.CreateMatrixData(n, n);

            this.d = new double[n];
            Array.Copy(d, 0, this.d, 0, n);

            this.e = new double[n];
            Array.Copy(e, 0, this.e, 1, n - 1);

            for (int i = 0; i < n; i++)
            {
                V[i][i] = 1;
            }

            SymmetricDiagonalize();

            InitOnDemandComputations();
        }
Exemplo n.º 8
0
        EigenvalueDecomposition(
            Matrix Arg
            )
        {
            double[][] A = Arg;
            n = Arg.ColumnCount;
            V = Matrix.CreateMatrixData(n, n);
            d = new double[n];
            e = new double[n];

            isSymmetric = true;
            for (int j = 0; (j < n) & isSymmetric; j++)
            {
                for (int i = 0; (i < n) & isSymmetric; i++)
                {
                    isSymmetric &= (A[i][j] == A[j][i]);
                }
            }

            if (isSymmetric)
            {
                for (int i = 0; i < n; i++)
                {
                    for (int j = 0; j < n; j++)
                    {
                        V[i][j] = A[i][j];
                    }
                }

                SymmetricTridiagonalize();

                SymmetricDiagonalize();
            }
            else
            {
                H = new double[n][];
                for (int i = 0; i < n; i++)
                {
                    double[] Hi = new double[n];
                    double[] Ai = A[i];

                    for (int j = 0; j < n; j++)
                    {
                        Hi[j] = Ai[j];
                    }

                    H[i] = Hi;
                }

                NonsymmetricReduceToHessenberg();

                NonsymmetricReduceHessenberToRealSchur();
            }

            _eigenValuesReal = new Vector(d);
            _eigenValuesImag = new Vector(e);
            _eigenValues     = ComplexVector.Create(d, e);

            InitOnDemandComputations();
        }
Exemplo n.º 9
0
        EigenvalueDecomposition(Matrix arg)
        {
            double[][] a = arg;
            _n = arg.ColumnCount;
            _v = Matrix.CreateMatrixData(_n, _n);
            _d = new double[_n];
            _e = new double[_n];

            _isSymmetric = true;
            for (int j = 0; (j < _n) & _isSymmetric; j++)
            {
                for (int i = 0; (i < _n) & _isSymmetric; i++)
                {
                    _isSymmetric &= (a[i][j] == a[j][i]);
                }
            }

            if (_isSymmetric)
            {
                for (int i = 0; i < _n; i++)
                {
                    for (int j = 0; j < _n; j++)
                    {
                        _v[i][j] = a[i][j];
                    }
                }

                SymmetricTridiagonalize();

                SymmetricDiagonalize();
            }
            else
            {
                _h = new double[_n][];
                for (int i = 0; i < _n; i++)
                {
                    double[] hi = new double[_n];
                    double[] ai = a[i];

                    for (int j = 0; j < _n; j++)
                    {
                        hi[j] = ai[j];
                    }

                    _h[i] = hi;
                }

                NonsymmetricReduceToHessenberg();

                NonsymmetricReduceHessenberToRealSchur();
            }

            _eigenValuesReal = new Vector(_d);
            _eigenValuesImag = new Vector(_e);
            _eigenValues     = ComplexVector.Create(_d, _e);

            InitOnDemandComputations();
        }
Exemplo n.º 10
0
 ToColumnMatrix()
 {
     double[][] m = Matrix.CreateMatrixData(_length, 1);
     for (int i = 0; i < m.Length; i++)
     {
         m[i][0] = _data[i];
     }
     return(new Matrix(m));
 }
Exemplo n.º 11
0
 ToRowMatrix()
 {
     double[][] m = Matrix.CreateMatrixData(1, _length);
     for (int i = 0; i < m.Length; i++)
     {
         m[0][i] = _data[i];
     }
     return(new Matrix(m));
 }
Exemplo n.º 12
0
        ComputePermutationMatrix()
        {
            int[]      pivot = Pivot;
            double[][] perm  = Matrix.CreateMatrixData(pivot.Length, pivot.Length);
            for (int i = 0; i < pivot.Length; i++)
            {
                perm[pivot[i]][i] = 1.0;
            }

            return(new Matrix(perm));
        }
Exemplo n.º 13
0
        Solve(
            Matrix B
            )
        {
            if (B.RowCount != _l.RowCount)
            {
                throw new ArgumentException(Resources.ArgumentMatrixSameRowDimension, "B");
            }

            if (!_isSymmetricPositiveDefinite)
            {
                throw new InvalidOperationException(Resources.ArgumentMatrixSymmetricPositiveDefinite);
            }

            int nx = B.ColumnCount;

            double[][] L  = _l;
            double[][] BB = B;
            double[][] X  = Matrix.CreateMatrixData(L.Length, nx);

            // Solve L*Y = B
            for (int i = 0; i < X.Length; i++)
            {
                for (int j = 0; j < nx; j++)
                {
                    double sum = BB[i][j];

                    for (int k = i - 1; k >= 0; k--)
                    {
                        sum -= L[i][k] * X[k][j];
                    }

                    X[i][j] = sum / L[i][i];
                }
            }

            // Solve L'*x = y
            for (int i = X.Length - 1; i >= 0; i--)
            {
                for (int j = 0; j < nx; j++)
                {
                    double sum = X[i][j];

                    for (int k = i + 1; k < X.Length; k++)
                    {
                        sum -= L[k][i] * X[k][j];
                    }

                    X[i][j] = sum / L[i][i];
                }
            }

            return(new Matrix(X));
        }
Exemplo n.º 14
0
        EigenvalueDecomposition(
            Matrix Arg
            )
        {
            double[][] A = Arg;
            n = Arg.ColumnCount;
            V = Matrix.CreateMatrixData(n, n);
            d = new double[n];
            e = new double[n];

            isSymmetric = true;
            for (int j = 0; (j < n) & isSymmetric; j++)
            {
                for (int i = 0; (i < n) & isSymmetric; i++)
                {
                    isSymmetric = (A[i][j] == A[j][i]);
                }
            }

            if (isSymmetric)
            {
                for (int i = 0; i < n; i++)
                {
                    for (int j = 0; j < n; j++)
                    {
                        V[i][j] = A[i][j];
                    }
                }

                SymmetricTridiagonalize();

                SymmetricDiagonalize();
            }
            else
            {
                H   = Matrix.CreateMatrixData(n, n);
                ort = new double[n];

                for (int j = 0; j < n; j++)
                {
                    for (int i = 0; i < n; i++)
                    {
                        H[i][j] = A[i][j];
                    }
                }

                NonsymmetricReduceToHessenberg();

                NonsymmetricReduceHessenberToRealSchur();
            }

            InitOnDemandComputations();
        }
        Solve(Matrix b)
        {
            if (b.RowCount != _l.RowCount)
            {
                throw new ArgumentException(Properties.LocalStrings.ArgumentMatrixSameRowDimension, "B");
            }

            if (!_isSymmetricPositiveDefinite)
            {
                throw new InvalidOperationException(Properties.LocalStrings.ArgumentMatrixSymmetricPositiveDefinite);
            }

            int nx = b.ColumnCount;

            double[][] l  = _l;
            double[][] bb = b;
            double[][] x  = Matrix.CreateMatrixData(l.Length, nx);

            // Solve L*Y = B
            for (int i = 0; i < x.Length; i++)
            {
                for (int j = 0; j < nx; j++)
                {
                    double sum = bb[i][j];

                    for (int k = i - 1; k >= 0; k--)
                    {
                        sum -= l[i][k] * x[k][j];
                    }

                    x[i][j] = sum / l[i][i];
                }
            }

            // Solve L'*x = y
            for (int i = x.Length - 1; i >= 0; i--)
            {
                for (int j = 0; j < nx; j++)
                {
                    double sum = x[i][j];

                    for (int k = i + 1; k < x.Length; k++)
                    {
                        sum -= l[k][i] * x[k][j];
                    }

                    x[i][j] = sum / l[i][i];
                }
            }

            return(new Matrix(x));
        }
Exemplo n.º 16
0
        ComputeUpperTriangularFactor()
        {
            double[][] u = Matrix.CreateMatrixData(_columnCount, _columnCount);
            for (int i = 0; i < _columnCount; i++)
            {
                for (int j = 0; j < _columnCount; j++)
                {
                    u[i][j] = (i <= j) ? _lu[i][j] : 0.0;
                }
            }

            return(new Matrix(u));
        }
        ComputeHouseholderVectors()
        {
            double[][] h = Matrix.CreateMatrixData(M, N);
            for (int i = 0; i < M; i++)
            {
                for (int j = 0; j < N; j++)
                {
                    h[i][j] = (i >= j) ? _qr[i][j] : 0.0;
                }
            }

            return(new Matrix(h));
        }
        ComputeDiagonalSingularValues()
        {
            double[][] X = Matrix.CreateMatrixData(n, n);
            for (int i = 0; i < n; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    X[i][j] = 0.0;
                }

                X[i][i] = this.s[i];
            }
            return(new Matrix(X));
        }
Exemplo n.º 19
0
 DyadicProduct(
     IVector u,
     IVector v
     )
 {
     double[][] m = Matrix.CreateMatrixData(u.Length, v.Length);
     for (int i = 0; i < u.Length; i++)
     {
         for (int j = 0; j < v.Length; j++)
         {
             m[i][j] = u[i] * v[j];
         }
     }
     return(new Matrix(m));
 }
Exemplo n.º 20
0
        CholeskyDecomposition(
            Matrix m
            )
        {
            if (m.RowCount != m.ColumnCount)
            {
                throw new InvalidOperationException(Resources.ArgumentMatrixSquare);
            }

            double[][] A = m;
            double[][] L = Matrix.CreateMatrixData(m.RowCount, m.RowCount);

            _isSymmetricPositiveDefinite = true; // ensure square

            for (int i = 0; i < L.Length; i++)
            {
                double diagonal = 0.0;
                for (int j = 0; j < i; j++)
                {
                    double sum = A[i][j];
                    for (int k = 0; k < j; k++)
                    {
                        sum -= L[j][k] * L[i][k];
                    }

                    L[i][j]   = sum /= L[j][j];
                    diagonal += sum * sum;

                    _isSymmetricPositiveDefinite &= (A[j][i] == A[i][j]); // ensure symmetry
                }

                diagonal = A[i][i] - diagonal;
                L[i][i]  = Math.Sqrt(Math.Max(diagonal, 0.0));

                _isSymmetricPositiveDefinite &= (diagonal > 0.0); // ensure positive definite

                // zero out resulting upper triangle.
                for (int j = i + 1; j < L.Length; j++)
                {
                    L[i][j] = 0.0;
                }
            }

            _l = new Matrix(L);
        }
        CholeskyDecomposition(Matrix m)
        {
            if (m.RowCount != m.ColumnCount)
            {
                throw new InvalidOperationException(Properties.LocalStrings.ArgumentMatrixSquare);
            }

            double[][] a = m;
            double[][] l = Matrix.CreateMatrixData(m.RowCount, m.RowCount);

            _isSymmetricPositiveDefinite = true; // ensure square

            for (int i = 0; i < l.Length; i++)
            {
                double diagonal = 0.0;
                for (int j = 0; j < i; j++)
                {
                    double sum = a[i][j];
                    for (int k = 0; k < j; k++)
                    {
                        sum -= l[j][k] * l[i][k];
                    }

                    l[i][j]   = sum /= l[j][j];
                    diagonal += sum * sum;

                    _isSymmetricPositiveDefinite &= (a[j][i] == a[i][j]); // ensure symmetry
                }

                diagonal = a[i][i] - diagonal;
                l[i][i]  = Math.Sqrt(Math.Max(diagonal, 0.0));

                _isSymmetricPositiveDefinite &= (diagonal > 0.0); // ensure positive definite

                // zero out resulting upper triangle.
                for (int j = i + 1; j < l.Length; j++)
                {
                    l[i][j] = 0.0;
                }
            }

            _l = new Matrix(l);
        }
Exemplo n.º 22
0
 ComputeHouseholderVectors()
 {
     double[][] H = Matrix.CreateMatrixData(m, n);
     for (int i = 0; i < m; i++)
     {
         for (int j = 0; j < n; j++)
         {
             if (i >= j)
             {
                 H[i][j] = QR[i][j];
             }
             else
             {
                 H[i][j] = 0.0;
             }
         }
     }
     return(new Matrix(H));
 }
Exemplo n.º 23
0
 ComputeUpperTriangularFactor()
 {
     double[][] U = Matrix.CreateMatrixData(_columnCount, _columnCount);
     for (int i = 0; i < _columnCount; i++)
     {
         for (int j = 0; j < _columnCount; j++)
         {
             if (i <= j)
             {
                 U[i][j] = LU[i][j];
             }
             else
             {
                 U[i][j] = 0.0;
             }
         }
     }
     return(new Matrix(U));
 }
Exemplo n.º 24
0
 ComputeBlockDiagonalMatrix()
 {
     double[][] D = Matrix.CreateMatrixData(n, n);
     for (int i = 0; i < n; i++)
     {
         for (int j = 0; j < n; j++)
         {
             D[i][j] = 0.0;
         }
         D[i][i] = d[i];
         if (e[i] > 0)
         {
             D[i][i + 1] = e[i];
         }
         else if (e[i] < 0)
         {
             D[i][i - 1] = e[i];
         }
     }
     return(new Matrix(D));
 }
Exemplo n.º 25
0
 ComputeUpperTriangularFactor()
 {
     double[][] R = Matrix.CreateMatrixData(n, n);
     for (int i = 0; i < n; i++)
     {
         for (int j = 0; j < n; j++)
         {
             if (i < j)
             {
                 R[i][j] = QR[i][j];
             }
             else if (i == j)
             {
                 R[i][j] = Rdiag[i];
             }
             else
             {
                 R[i][j] = 0.0;
             }
         }
     }
     return(new Matrix(R));
 }
Exemplo n.º 26
0
 ComputeLowerTriangularFactor()
 {
     double[][] L = Matrix.CreateMatrixData(_rowCount, _columnCount);
     for (int i = 0; i < L.Length; i++)
     {
         for (int j = 0; j < _columnCount; j++)
         {
             if (i > j)
             {
                 L[i][j] = LU[i][j];
             }
             else if (i == j)
             {
                 L[i][j] = 1.0;
             }
             else
             {
                 L[i][j] = 0.0;
             }
         }
     }
     return(new Matrix(L));
 }
Exemplo n.º 27
0
        ComputeBlockDiagonalMatrix()
        {
            double[][] d = Matrix.CreateMatrixData(_n, _n);
            for (int i = 0; i < _n; i++)
            {
                for (int j = 0; j < _n; j++)
                {
                    d[i][j] = 0.0;
                }

                d[i][i] = _d[i];

                if (_e[i] > 0)
                {
                    d[i][i + 1] = _e[i];
                }
                else if (_e[i] < 0)
                {
                    d[i][i - 1] = _e[i];
                }
            }

            return(new Matrix(d));
        }
Exemplo n.º 28
0
        SingularValueDecomposition(IMatrix <double> arg)
        {
            _transpose = (arg.RowCount < arg.ColumnCount);

            // Derived from LINPACK code.
            // Initialize.
            double[][] a;
            if (_transpose)
            {
                // copy of internal data, independent of Arg
                a  = Matrix.Transpose(arg).GetArray();
                _m = arg.ColumnCount;
                _n = arg.RowCount;
            }
            else
            {
                a  = arg.CopyToJaggedArray();
                _m = arg.RowCount;
                _n = arg.ColumnCount;
            }

            int nu = Math.Min(_m, _n);

            double[]   s = new double[Math.Min(_m + 1, _n)];
            double[][] u = Matrix.CreateMatrixData(_m, nu);
            double[][] v = Matrix.CreateMatrixData(_n, _n);

            double[] e    = new double[_n];
            double[] work = new double[_m];

            /*
             * Reduce A to bidiagonal form, storing the diagonal elements
             * in s and the super-diagonal elements in e.
             */

            int nct = Math.Min(_m - 1, _n);
            int nrt = Math.Max(0, Math.Min(_n - 2, _m));

            for (int k = 0; k < Math.Max(nct, nrt); k++)
            {
                if (k < nct)
                {
                    // Compute the transformation for the k-th column and
                    // place the k-th diagonal in s[k].
                    // Compute 2-norm of k-th column without under/overflow.
                    s[k] = 0;

                    for (int i = k; i < _m; i++)
                    {
                        s[k] = Fn.Hypot(s[k], a[i][k]);
                    }

                    if (s[k] != 0.0)
                    {
                        if (a[k][k] < 0.0)
                        {
                            s[k] = -s[k];
                        }

                        for (int i = k; i < _m; i++)
                        {
                            a[i][k] /= s[k];
                        }

                        a[k][k] += 1.0;
                    }

                    s[k] = -s[k];
                }

                for (int j = k + 1; j < _n; j++)
                {
                    if ((k < nct) & (s[k] != 0.0))
                    {
                        /* Apply the transformation */

                        double t = 0;
                        for (int i = k; i < _m; i++)
                        {
                            t += a[i][k] * a[i][j];
                        }

                        t = (-t) / a[k][k];
                        for (int i = k; i < _m; i++)
                        {
                            a[i][j] += t * a[i][k];
                        }
                    }

                    /*
                     * Place the k-th row of A into e for the
                     * subsequent calculation of the row transformation.
                     */

                    e[j] = a[k][j];
                }

                if (k < nct)
                {
                    /*
                     * Place the transformation in U for subsequent back
                     * multiplication.
                     */

                    for (int i = k; i < _m; i++)
                    {
                        u[i][k] = a[i][k];
                    }
                }

                if (k < nrt)
                {
                    // Compute the k-th row transformation and place the
                    // k-th super-diagonal in e[k].
                    // Compute 2-norm without under/overflow.
                    e[k] = 0;

                    for (int i = k + 1; i < _n; i++)
                    {
                        e[k] = Fn.Hypot(e[k], e[i]);
                    }

                    if (e[k] != 0.0)
                    {
                        if (e[k + 1] < 0.0)
                        {
                            e[k] = -e[k];
                        }

                        for (int i = k + 1; i < _n; i++)
                        {
                            e[i] /= e[k];
                        }

                        e[k + 1] += 1.0;
                    }

                    e[k] = -e[k];

                    if ((k + 1 < _m) & (e[k] != 0.0))
                    {
                        /* Apply the transformation */

                        for (int i = k + 1; i < _m; i++)
                        {
                            work[i] = 0.0;
                        }

                        for (int j = k + 1; j < _n; j++)
                        {
                            for (int i = k + 1; i < _m; i++)
                            {
                                work[i] += e[j] * a[i][j];
                            }
                        }

                        for (int j = k + 1; j < _n; j++)
                        {
                            double t = (-e[j]) / e[k + 1];
                            for (int i = k + 1; i < _m; i++)
                            {
                                a[i][j] += t * work[i];
                            }
                        }
                    }

                    /*
                     * Place the transformation in V for subsequent
                     * back multiplication.
                     */

                    for (int i = k + 1; i < _n; i++)
                    {
                        v[i][k] = e[i];
                    }
                }
            }

            /* Set up the final bidiagonal matrix or order p. */

            int p = Math.Min(_n, _m + 1);

            if (nct < _n)
            {
                s[nct] = a[nct][nct];
            }

            if (_m < p)
            {
                s[p - 1] = 0.0;
            }

            if (nrt + 1 < p)
            {
                e[nrt] = a[nrt][p - 1];
            }

            e[p - 1] = 0.0;

            /* If required, generate U */

            for (int j = nct; j < nu; j++)
            {
                for (int i = 0; i < _m; i++)
                {
                    u[i][j] = 0.0;
                }

                u[j][j] = 1.0;
            }

            for (int k = nct - 1; k >= 0; k--)
            {
                if (s[k] != 0.0)
                {
                    for (int j = k + 1; j < nu; j++)
                    {
                        double t = 0;
                        for (int i = k; i < _m; i++)
                        {
                            t += u[i][k] * u[i][j];
                        }

                        t = (-t) / u[k][k];
                        for (int i = k; i < _m; i++)
                        {
                            u[i][j] += t * u[i][k];
                        }
                    }

                    for (int i = k; i < _m; i++)
                    {
                        u[i][k] = -u[i][k];
                    }

                    u[k][k] = 1.0 + u[k][k];
                    for (int i = 0; i < k - 1; i++)
                    {
                        u[i][k] = 0.0;
                    }
                }
                else
                {
                    for (int i = 0; i < _m; i++)
                    {
                        u[i][k] = 0.0;
                    }

                    u[k][k] = 1.0;
                }
            }

            /* If required, generate V */

            for (int k = _n - 1; k >= 0; k--)
            {
                if ((k < nrt) & (e[k] != 0.0))
                {
                    for (int j = k + 1; j < nu; j++)
                    {
                        double t = 0;
                        for (int i = k + 1; i < _n; i++)
                        {
                            t += v[i][k] * v[i][j];
                        }

                        t = (-t) / v[k + 1][k];
                        for (int i = k + 1; i < _n; i++)
                        {
                            v[i][j] += t * v[i][k];
                        }
                    }
                }

                for (int i = 0; i < _n; i++)
                {
                    v[i][k] = 0.0;
                }

                v[k][k] = 1.0;
            }

            /* Main iteration loop for the singular values */

            int    pp   = p - 1;
            int    iter = 0;
            double eps  = Number.PositiveRelativeAccuracy;

            while (p > 0)
            {
                int           k;
                IterationStep step;

                /* Here is where a test for too many iterations would go */

                /*
                 * This section of the program inspects for
                 * negligible elements in the s and e arrays.  On
                 * completion the variables kase and k are set as follows.
                 *
                 * DeflateNeglible:  if s[p] and e[k-1] are negligible and k<p
                 * SplitAtNeglible:  if s[k] is negligible and k<p
                 * QR:               if e[k-1] is negligible, k<p, and s[k], ..., s[p] are not negligible.
                 * Convergence:      if e[p-1] is negligible.
                 */

                for (k = p - 2; k >= 0; k--)
                {
                    if (Math.Abs(e[k]) <= eps * (Math.Abs(s[k]) + Math.Abs(s[k + 1])))
                    {
                        e[k] = 0.0;
                        break;
                    }
                }

                if (k == p - 2)
                {
                    step = IterationStep.Convergence;
                }
                else
                {
                    int ks;
                    for (ks = p - 1; ks >= k; ks--)
                    {
                        if (ks == k)
                        {
                            break;
                        }

                        double t = (ks != p ? Math.Abs(e[ks]) : 0.0) + (ks != k + 1 ? Math.Abs(e[ks - 1]) : 0.0);
                        if (Math.Abs(s[ks]) <= eps * t)
                        {
                            s[ks] = 0.0;
                            break;
                        }
                    }

                    if (ks == k)
                    {
                        step = IterationStep.QR;
                    }
                    else if (ks == p - 1)
                    {
                        step = IterationStep.DeflateNeglible;
                    }
                    else
                    {
                        step = IterationStep.SplitAtNeglible;
                        k    = ks;
                    }
                }

                k++;

                /* Perform the task indicated by 'step'. */

                switch (step)
                {
                // Deflate negligible s(p).
                case IterationStep.DeflateNeglible:
                {
                    double f = e[p - 2];
                    e[p - 2] = 0.0;
                    for (int j = p - 2; j >= k; j--)
                    {
                        double t  = Fn.Hypot(s[j], f);
                        double cs = s[j] / t;
                        double sn = f / t;
                        s[j] = t;

                        if (j != k)
                        {
                            f        = (-sn) * e[j - 1];
                            e[j - 1] = cs * e[j - 1];
                        }

                        for (int i = 0; i < _n; i++)
                        {
                            t           = (cs * v[i][j]) + (sn * v[i][p - 1]);
                            v[i][p - 1] = ((-sn) * v[i][j]) + (cs * v[i][p - 1]);
                            v[i][j]     = t;
                        }
                    }
                }

                break;

                // Split at negligible s(k)
                case IterationStep.SplitAtNeglible:
                {
                    double f = e[k - 1];
                    e[k - 1] = 0.0;
                    for (int j = k; j < p; j++)
                    {
                        double t  = Fn.Hypot(s[j], f);
                        double cs = s[j] / t;
                        double sn = f / t;
                        s[j] = t;
                        f    = (-sn) * e[j];
                        e[j] = cs * e[j];

                        for (int i = 0; i < _m; i++)
                        {
                            t           = (cs * u[i][j]) + (sn * u[i][k - 1]);
                            u[i][k - 1] = ((-sn) * u[i][j]) + (cs * u[i][k - 1]);
                            u[i][j]     = t;
                        }
                    }
                }

                break;

                // Perform one qr step.
                case IterationStep.QR:
                {
                    /* Calculate the shift */

                    double scale = Math.Max(Math.Max(Math.Max(Math.Max(Math.Abs(s[p - 1]), Math.Abs(s[p - 2])), Math.Abs(e[p - 2])), Math.Abs(s[k])), Math.Abs(e[k]));
                    double sp    = s[p - 1] / scale;
                    double spm1  = s[p - 2] / scale;
                    double epm1  = e[p - 2] / scale;
                    double sk    = s[k] / scale;
                    double ek    = e[k] / scale;
                    double b     = (((spm1 + sp) * (spm1 - sp)) + (epm1 * epm1)) / 2.0;
                    double c     = (sp * epm1) * (sp * epm1);
                    double shift = 0.0;
                    if ((b != 0.0) | (c != 0.0))
                    {
                        shift = Math.Sqrt((b * b) + c);

                        if (b < 0.0)
                        {
                            shift = -shift;
                        }

                        shift = c / (b + shift);
                    }

                    double f = ((sk + sp) * (sk - sp)) + shift;
                    double g = sk * ek;

                    /* Chase zeros */

                    for (int j = k; j < p - 1; j++)
                    {
                        double t  = Fn.Hypot(f, g);
                        double cs = f / t;
                        double sn = g / t;

                        if (j != k)
                        {
                            e[j - 1] = t;
                        }

                        f        = (cs * s[j]) + (sn * e[j]);
                        e[j]     = (cs * e[j]) - (sn * s[j]);
                        g        = sn * s[j + 1];
                        s[j + 1] = cs * s[j + 1];

                        for (int i = 0; i < _n; i++)
                        {
                            t           = (cs * v[i][j]) + (sn * v[i][j + 1]);
                            v[i][j + 1] = ((-sn) * v[i][j]) + (cs * v[i][j + 1]);
                            v[i][j]     = t;
                        }

                        t        = Fn.Hypot(f, g);
                        cs       = f / t;
                        sn       = g / t;
                        s[j]     = t;
                        f        = (cs * e[j]) + (sn * s[j + 1]);
                        s[j + 1] = ((-sn) * e[j]) + (cs * s[j + 1]);
                        g        = sn * e[j + 1];
                        e[j + 1] = cs * e[j + 1];

                        if (j < _m - 1)
                        {
                            for (int i = 0; i < _m; i++)
                            {
                                t           = (cs * u[i][j]) + (sn * u[i][j + 1]);
                                u[i][j + 1] = ((-sn) * u[i][j]) + (cs * u[i][j + 1]);
                                u[i][j]     = t;
                            }
                        }
                    }

                    e[p - 2] = f;
                    iter     = iter + 1;
                }

                break;

                // Convergence.
                case IterationStep.Convergence:
                {
                    /* Make the singular values positive */

                    if (s[k] <= 0.0)
                    {
                        s[k] = (s[k] < 0.0 ? -s[k] : 0.0);

                        for (int i = 0; i <= pp; i++)
                        {
                            v[i][k] = -v[i][k];
                        }
                    }

                    /* Order the singular values */

                    while (k < pp)
                    {
                        if (s[k] >= s[k + 1])
                        {
                            break;
                        }

                        double t = s[k];
                        s[k]     = s[k + 1];
                        s[k + 1] = t;

                        if (k < _n - 1)
                        {
                            for (int i = 0; i < _n; i++)
                            {
                                t           = v[i][k + 1];
                                v[i][k + 1] = v[i][k];
                                v[i][k]     = t;
                            }
                        }

                        if (k < _m - 1)
                        {
                            for (int i = 0; i < _m; i++)
                            {
                                t           = u[i][k + 1];
                                u[i][k + 1] = u[i][k];
                                u[i][k]     = t;
                            }
                        }

                        k++;
                    }

                    iter = 0;
                    p--;
                }

                break;
                }
            }

            // (vermorel) transposing the results if needed
            if (_transpose)
            {
                // swaping U and V
                double[][] temp = v;
                v = u;
                u = temp;
            }

            _u        = new Matrix(u);
            _v        = new Matrix(v);
            _singular = new Vector(s);

            InitOnDemandComputations();
        }
Exemplo n.º 29
0
        SingularValueDecomposition(
            Matrix Arg
            )
        {
            transpose = (Arg.RowCount < Arg.ColumnCount);

            // Derived from LINPACK code.
            // Initialize.
            double[][] A;
            if (transpose)
            {
                // copy of internal data, independent of Arg
                A = Matrix.Transpose(Arg).GetArray();
                m = Arg.ColumnCount;
                n = Arg.RowCount;
            }
            else
            {
                A = Arg.CopyToJaggedArray();
                m = Arg.RowCount;
                n = Arg.ColumnCount;
            }

            int nu = Math.Min(m, n);

            double[]   s = new double[Math.Min(m + 1, n)];
            double[][] U = Matrix.CreateMatrixData(m, nu);
            double[][] V = Matrix.CreateMatrixData(n, n);

            double[] e     = new double[n];
            double[] work  = new double[m];
            bool     wantu = true;
            bool     wantv = true;

            // Reduce A to bidiagonal form, storing the diagonal elements
            // in s and the super-diagonal elements in e.

            int nct = Math.Min(m - 1, n);
            int nrt = Math.Max(0, Math.Min(n - 2, m));

            for (int k = 0; k < Math.Max(nct, nrt); k++)
            {
                if (k < nct)
                {
                    // Compute the transformation for the k-th column and
                    // place the k-th diagonal in s[k].
                    // Compute 2-norm of k-th column without under/overflow.
                    s[k] = 0;

                    for (int i = k; i < m; i++)
                    {
                        s[k] = Fn.Hypot(s[k], A[i][k]);
                    }

                    if (s[k] != 0.0)
                    {
                        if (A[k][k] < 0.0)
                        {
                            s[k] = -s[k];
                        }

                        for (int i = k; i < m; i++)
                        {
                            A[i][k] /= s[k];
                        }

                        A[k][k] += 1.0;
                    }

                    s[k] = -s[k];
                }

                for (int j = k + 1; j < n; j++)
                {
                    if ((k < nct) & (s[k] != 0.0))
                    {
                        // Apply the transformation.

                        double t = 0;
                        for (int i = k; i < m; i++)
                        {
                            t += A[i][k] * A[i][j];
                        }

                        t = (-t) / A[k][k];
                        for (int i = k; i < m; i++)
                        {
                            A[i][j] += t * A[i][k];
                        }
                    }

                    // Place the k-th row of A into e for the
                    // subsequent calculation of the row transformation.

                    e[j] = A[k][j];
                }

                if (wantu & (k < nct))
                {
                    // Place the transformation in U for subsequent back
                    // multiplication.

                    for (int i = k; i < m; i++)
                    {
                        U[i][k] = A[i][k];
                    }
                }

                if (k < nrt)
                {
                    // Compute the k-th row transformation and place the
                    // k-th super-diagonal in e[k].
                    // Compute 2-norm without under/overflow.
                    e[k] = 0;

                    for (int i = k + 1; i < n; i++)
                    {
                        e[k] = Fn.Hypot(e[k], e[i]);
                    }

                    if (e[k] != 0.0)
                    {
                        if (e[k + 1] < 0.0)
                        {
                            e[k] = -e[k];
                        }

                        for (int i = k + 1; i < n; i++)
                        {
                            e[i] /= e[k];
                        }

                        e[k + 1] += 1.0;
                    }

                    e[k] = -e[k];

                    if ((k + 1 < m) & (e[k] != 0.0))
                    {
                        // Apply the transformation.

                        for (int i = k + 1; i < m; i++)
                        {
                            work[i] = 0.0;
                        }

                        for (int j = k + 1; j < n; j++)
                        {
                            for (int i = k + 1; i < m; i++)
                            {
                                work[i] += e[j] * A[i][j];
                            }
                        }

                        for (int j = k + 1; j < n; j++)
                        {
                            double t = (-e[j]) / e[k + 1];
                            for (int i = k + 1; i < m; i++)
                            {
                                A[i][j] += t * work[i];
                            }
                        }
                    }

                    if (wantv)
                    {
                        // Place the transformation in V for subsequent
                        // back multiplication.

                        for (int i = k + 1; i < n; i++)
                        {
                            V[i][k] = e[i];
                        }
                    }
                }
            }

            // Set up the final bidiagonal matrix or order p.

            int p = Math.Min(n, m + 1);

            if (nct < n)
            {
                s[nct] = A[nct][nct];
            }

            if (m < p)
            {
                s[p - 1] = 0.0;
            }

            if (nrt + 1 < p)
            {
                e[nrt] = A[nrt][p - 1];
            }

            e[p - 1] = 0.0;

            // If required, generate U.

            if (wantu)
            {
                for (int j = nct; j < nu; j++)
                {
                    for (int i = 0; i < m; i++)
                    {
                        U[i][j] = 0.0;
                    }

                    U[j][j] = 1.0;
                }

                for (int k = nct - 1; k >= 0; k--)
                {
                    if (s[k] != 0.0)
                    {
                        for (int j = k + 1; j < nu; j++)
                        {
                            double t = 0;
                            for (int i = k; i < m; i++)
                            {
                                t += U[i][k] * U[i][j];
                            }

                            t = (-t) / U[k][k];
                            for (int i = k; i < m; i++)
                            {
                                U[i][j] += t * U[i][k];
                            }
                        }

                        for (int i = k; i < m; i++)
                        {
                            U[i][k] = -U[i][k];
                        }

                        U[k][k] = 1.0 + U[k][k];
                        for (int i = 0; i < k - 1; i++)
                        {
                            U[i][k] = 0.0;
                        }
                    }
                    else
                    {
                        for (int i = 0; i < m; i++)
                        {
                            U[i][k] = 0.0;
                        }

                        U[k][k] = 1.0;
                    }
                }
            }

            // If required, generate V.

            if (wantv)
            {
                for (int k = n - 1; k >= 0; k--)
                {
                    if ((k < nrt) & (e[k] != 0.0))
                    {
                        for (int j = k + 1; j < nu; j++)
                        {
                            double t = 0;
                            for (int i = k + 1; i < n; i++)
                            {
                                t += V[i][k] * V[i][j];
                            }

                            t = (-t) / V[k + 1][k];
                            for (int i = k + 1; i < n; i++)
                            {
                                V[i][j] += t * V[i][k];
                            }
                        }
                    }

                    for (int i = 0; i < n; i++)
                    {
                        V[i][k] = 0.0;
                    }

                    V[k][k] = 1.0;
                }
            }

            // Main iteration loop for the singular values.

            int    pp   = p - 1;
            int    iter = 0;
            double eps  = Number.PositiveRelativeAccuracy;

            while (p > 0)
            {
                int k, kase;

                // Here is where a test for too many iterations would go.

                // This section of the program inspects for
                // negligible elements in the s and e arrays.  On
                // completion the variables kase and k are set as follows.

                // kase = 1     if s(p) and e[k-1] are negligible and k<p
                // kase = 2     if s(k) is negligible and k<p
                // kase = 3     if e[k-1] is negligible, k<p, and
                //              s(k), ..., s(p) are not negligible (qr step).
                // kase = 4     if e(p-1) is negligible (convergence).

                for (k = p - 2; k >= -1; k--)
                {
                    if (k == -1)
                    {
                        break;
                    }

                    if (Math.Abs(e[k]) <= eps * (Math.Abs(s[k]) + Math.Abs(s[k + 1])))
                    {
                        e[k] = 0.0;
                        break;
                    }
                }

                if (k == p - 2)
                {
                    kase = 4;
                }
                else
                {
                    int ks;
                    for (ks = p - 1; ks >= k; ks--)
                    {
                        if (ks == k)
                        {
                            break;
                        }

                        double t = (ks != p ? Math.Abs(e[ks]) : 0.0) + (ks != k + 1 ? Math.Abs(e[ks - 1]) : 0.0);
                        if (Math.Abs(s[ks]) <= eps * t)
                        {
                            s[ks] = 0.0;
                            break;
                        }
                    }

                    if (ks == k)
                    {
                        kase = 3;
                    }
                    else if (ks == p - 1)
                    {
                        kase = 1;
                    }
                    else
                    {
                        kase = 2;
                        k    = ks;
                    }
                }

                k++;

                // Perform the task indicated by kase.

                switch (kase)
                {
                // Deflate negligible s(p).
                case 1:
                {
                    double f = e[p - 2];
                    e[p - 2] = 0.0;
                    for (int j = p - 2; j >= k; j--)
                    {
                        double t  = Fn.Hypot(s[j], f);
                        double cs = s[j] / t;
                        double sn = f / t;
                        s[j] = t;

                        if (j != k)
                        {
                            f        = (-sn) * e[j - 1];
                            e[j - 1] = cs * e[j - 1];
                        }

                        if (wantv)
                        {
                            for (int i = 0; i < n; i++)
                            {
                                t           = cs * V[i][j] + sn * V[i][p - 1];
                                V[i][p - 1] = (-sn) * V[i][j] + cs * V[i][p - 1];
                                V[i][j]     = t;
                            }
                        }
                    }
                }

                break;

                // Split at negligible s(k)
                case 2:
                {
                    double f = e[k - 1];
                    e[k - 1] = 0.0;
                    for (int j = k; j < p; j++)
                    {
                        double t  = Fn.Hypot(s[j], f);
                        double cs = s[j] / t;
                        double sn = f / t;
                        s[j] = t;
                        f    = (-sn) * e[j];
                        e[j] = cs * e[j];
                        if (wantu)
                        {
                            for (int i = 0; i < m; i++)
                            {
                                t           = cs * U[i][j] + sn * U[i][k - 1];
                                U[i][k - 1] = (-sn) * U[i][j] + cs * U[i][k - 1];
                                U[i][j]     = t;
                            }
                        }
                    }
                }

                break;

                // Perform one qr step.
                case 3:
                {
                    // Calculate the shift.

                    double scale = Math.Max(Math.Max(Math.Max(Math.Max(Math.Abs(s[p - 1]), Math.Abs(s[p - 2])), Math.Abs(e[p - 2])), Math.Abs(s[k])), Math.Abs(e[k]));
                    double sp    = s[p - 1] / scale;
                    double spm1  = s[p - 2] / scale;
                    double epm1  = e[p - 2] / scale;
                    double sk    = s[k] / scale;
                    double ek    = e[k] / scale;
                    double b     = ((spm1 + sp) * (spm1 - sp) + epm1 * epm1) / 2.0;
                    double c     = (sp * epm1) * (sp * epm1);
                    double shift = 0.0;
                    if ((b != 0.0) | (c != 0.0))
                    {
                        shift = Math.Sqrt(b * b + c);

                        if (b < 0.0)
                        {
                            shift = -shift;
                        }

                        shift = c / (b + shift);
                    }

                    double f = (sk + sp) * (sk - sp) + shift;
                    double g = sk * ek;

                    // Chase zeros.

                    for (int j = k; j < p - 1; j++)
                    {
                        double t  = Fn.Hypot(f, g);
                        double cs = f / t;
                        double sn = g / t;

                        if (j != k)
                        {
                            e[j - 1] = t;
                        }

                        f        = cs * s[j] + sn * e[j];
                        e[j]     = cs * e[j] - sn * s[j];
                        g        = sn * s[j + 1];
                        s[j + 1] = cs * s[j + 1];

                        if (wantv)
                        {
                            for (int i = 0; i < n; i++)
                            {
                                t           = cs * V[i][j] + sn * V[i][j + 1];
                                V[i][j + 1] = (-sn) * V[i][j] + cs * V[i][j + 1];
                                V[i][j]     = t;
                            }
                        }

                        t        = Fn.Hypot(f, g);
                        cs       = f / t;
                        sn       = g / t;
                        s[j]     = t;
                        f        = cs * e[j] + sn * s[j + 1];
                        s[j + 1] = (-sn) * e[j] + cs * s[j + 1];
                        g        = sn * e[j + 1];
                        e[j + 1] = cs * e[j + 1];

                        if (wantu && (j < m - 1))
                        {
                            for (int i = 0; i < m; i++)
                            {
                                t           = cs * U[i][j] + sn * U[i][j + 1];
                                U[i][j + 1] = (-sn) * U[i][j] + cs * U[i][j + 1];
                                U[i][j]     = t;
                            }
                        }
                    }

                    e[p - 2] = f;
                    iter     = iter + 1;
                }

                break;

                // Convergence.


                case 4:
                {
                    // Make the singular values positive.

                    if (s[k] <= 0.0)
                    {
                        s[k] = (s[k] < 0.0 ? -s[k] : 0.0);
                        if (wantv)
                        {
                            for (int i = 0; i <= pp; i++)
                            {
                                V[i][k] = -V[i][k];
                            }
                        }
                    }

                    // Order the singular values.

                    while (k < pp)
                    {
                        if (s[k] >= s[k + 1])
                        {
                            break;
                        }

                        double t = s[k];
                        s[k]     = s[k + 1];
                        s[k + 1] = t;

                        if (wantv && (k < n - 1))
                        {
                            for (int i = 0; i < n; i++)
                            {
                                t           = V[i][k + 1];
                                V[i][k + 1] = V[i][k];
                                V[i][k]     = t;
                            }
                        }

                        if (wantu && (k < m - 1))
                        {
                            for (int i = 0; i < m; i++)
                            {
                                t           = U[i][k + 1];
                                U[i][k + 1] = U[i][k];
                                U[i][k]     = t;
                            }
                        }

                        k++;
                    }

                    iter = 0;
                    p--;
                }

                break;
                }
            }

            // (vermorel) transposing the results if needed
            if (transpose)
            {
                // swaping U and V
                double[][] T = V;
                V = U;
                U = T;
            }

            _u        = new Matrix(U);
            _v        = new Matrix(V);
            _singular = new Vector(s);

            InitOnDemandComputations();
        }