Make all compute() methods return a reference to *this.

Eigen/src/Eigenvalues/ComplexEigenSolver.h

@@ -200,6 +200,7 @@ template<typename _MatrixType> class ComplexEigenSolver
       * \param[in]  computeEigenvectors  If true, both the eigenvectors and the
       *    eigenvalues are computed; if false, only the eigenvalues are
       *    computed. 
+      * \returns    Reference to \c *this
       *
       * This function computes the eigenvalues of the complex matrix \p matrix.
       * The eigenvalues() function can be used to retrieve them.  If 
@@ -217,7 +218,7 @@ template<typename _MatrixType> class ComplexEigenSolver
       * Example: \include ComplexEigenSolver_compute.cpp
       * Output: \verbinclude ComplexEigenSolver_compute.out
       */
-    void compute(const MatrixType& matrix, bool computeEigenvectors = true);
+    ComplexEigenSolver& compute(const MatrixType& matrix, bool computeEigenvectors = true);
 
   protected:
     EigenvectorType m_eivec;
@@ -230,7 +231,7 @@ template<typename _MatrixType> class ComplexEigenSolver
 
 
 template<typename MatrixType>
-void ComplexEigenSolver<MatrixType>::compute(const MatrixType& matrix, bool computeEigenvectors)
+ComplexEigenSolver<MatrixType>& ComplexEigenSolver<MatrixType>::compute(const MatrixType& matrix, bool computeEigenvectors)
 {
   // this code is inspired from Jampack
   assert(matrix.cols() == matrix.rows());
@@ -292,6 +293,8 @@ void ComplexEigenSolver<MatrixType>::compute(const MatrixType& matrix, bool comp
 	m_eivec.col(i).swap(m_eivec.col(k));
     }
   }
+
+  return *this;
 }
 
 

Eigen/src/Eigenvalues/ComplexSchur.h

@@ -175,6 +175,7 @@ template<typename _MatrixType> class ComplexSchur
       * 
       * \param[in]  matrix  Square matrix whose Schur decomposition is to be computed.
       * \param[in]  computeU  If true, both T and U are computed; if false, only T is computed.
+      * \returns    Reference to \c *this
       *
       * The Schur decomposition is computed by first reducing the
       * matrix to Hessenberg form using the class
@@ -189,7 +190,7 @@ template<typename _MatrixType> class ComplexSchur
       * Example: \include ComplexSchur_compute.cpp
       * Output: \verbinclude ComplexSchur_compute.out
       */
-    void compute(const MatrixType& matrix, bool computeU = true);
+    ComplexSchur& compute(const MatrixType& matrix, bool computeU = true);
 
   protected:
     ComplexMatrixType m_matT, m_matU;
@@ -296,7 +297,7 @@ typename ComplexSchur<MatrixType>::ComplexScalar ComplexSchur<MatrixType>::compu
 
 
 template<typename MatrixType>
-void ComplexSchur<MatrixType>::compute(const MatrixType& matrix, bool computeU)
+ComplexSchur<MatrixType>& ComplexSchur<MatrixType>::compute(const MatrixType& matrix, bool computeU)
 {
   m_matUisUptodate = false;
   ei_assert(matrix.cols() == matrix.rows());
@@ -307,11 +308,12 @@ void ComplexSchur<MatrixType>::compute(const MatrixType& matrix, bool computeU)
     if(computeU)  m_matU = ComplexMatrixType::Identity(1,1);
     m_isInitialized = true;
     m_matUisUptodate = computeU;
-    return;
+    return *this;
   }
 
   ei_complex_schur_reduce_to_hessenberg<MatrixType, NumTraits<Scalar>::IsComplex>::run(*this, matrix, computeU);
   reduceToTriangularForm(computeU);
+  return *this;
 }
 
 /* Reduce given matrix to Hessenberg form */

Eigen/src/Eigenvalues/HessenbergDecomposition.h

@@ -141,6 +141,7 @@ template<typename _MatrixType> class HessenbergDecomposition
     /** \brief Computes Hessenberg decomposition of given matrix. 
       * 
       * \param[in]  matrix  Square matrix whose Hessenberg decomposition is to be computed.
+      * \returns    Reference to \c *this
       *
       * The Hessenberg decomposition is computed by bringing the columns of the
       * matrix successively in the required form using Householder reflections
@@ -154,17 +155,18 @@ template<typename _MatrixType> class HessenbergDecomposition
       * Example: \include HessenbergDecomposition_compute.cpp
       * Output: \verbinclude HessenbergDecomposition_compute.out
       */
-    void compute(const MatrixType& matrix)
+    HessenbergDecomposition& compute(const MatrixType& matrix)
     {
       m_matrix = matrix;
       if(matrix.rows()<2)
       {
 	m_isInitialized = true;
-        return;
+        return *this;
       }
       m_hCoeffs.resize(matrix.rows()-1,1);
       _compute(m_matrix, m_hCoeffs, m_temp);
       m_isInitialized = true;
+      return *this;
     }
 
     /** \brief Returns the Householder coefficients.

Eigen/src/Eigenvalues/RealSchur.h

@@ -161,6 +161,7 @@ template<typename _MatrixType> class RealSchur
       * 
       * \param[in]  matrix    Square matrix whose Schur decomposition is to be computed.
       * \param[in]  computeU  If true, both T and U are computed; if false, only T is computed.
+      * \returns    Reference to \c *this
       *
       * The Schur decomposition is computed by first reducing the matrix to
       * Hessenberg form using the class HessenbergDecomposition. The Hessenberg
@@ -173,7 +174,7 @@ template<typename _MatrixType> class RealSchur
       * Example: \include RealSchur_compute.cpp
       * Output: \verbinclude RealSchur_compute.out
       */
-    void compute(const MatrixType& matrix, bool computeU = true);
+    RealSchur& compute(const MatrixType& matrix, bool computeU = true);
 
   private:
     
@@ -196,7 +197,7 @@ template<typename _MatrixType> class RealSchur
 
 
 template<typename MatrixType>
-void RealSchur<MatrixType>::compute(const MatrixType& matrix, bool computeU)
+RealSchur<MatrixType>& RealSchur<MatrixType>::compute(const MatrixType& matrix, bool computeU)
 {
   assert(matrix.cols() == matrix.rows());
 
@@ -251,6 +252,7 @@ void RealSchur<MatrixType>::compute(const MatrixType& matrix, bool computeU)
 
   m_isInitialized = true;
   m_matUisUptodate = computeU;
+  return *this;
 }
 
 /** \internal Computes and returns vector L1 norm of T */

Eigen/src/Eigenvalues/Tridiagonalization.h

@@ -137,6 +137,7 @@ template<typename _MatrixType> class Tridiagonalization
       * 
       * \param[in]  matrix  Selfadjoint matrix whose tridiagonal decomposition
       * is to be computed.
+      * \returns    Reference to \c *this
       *
       * The tridiagonal decomposition is computed by bringing the columns of
       * the matrix successively in the required form using Householder
@@ -149,12 +150,13 @@ template<typename _MatrixType> class Tridiagonalization
       * Example: \include Tridiagonalization_compute.cpp
       * Output: \verbinclude Tridiagonalization_compute.out
       */
-    void compute(const MatrixType& matrix)
+    Tridiagonalization& compute(const MatrixType& matrix)
     {
       m_matrix = matrix;
       m_hCoeffs.resize(matrix.rows()-1, 1);
       _compute(m_matrix, m_hCoeffs);
       m_isInitialized = true;
+      return *this;
     }
 
     /** \brief Returns the Householder coefficients.