Fix GeneralizedEigenSolver::info() and Asserts

(cherry picked from commit a7c1cac18bfef26ec61a73c1619ccf0f9b734745)

Eigen/src/Eigenvalues/GeneralizedEigenSolver.h

@@ -119,8 +119,8 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       : m_eivec(),
         m_alphas(),
         m_betas(),
-        m_valuesOkay(false),
+        m_computeEigenvectors(false),
-        m_vectorsOkay(false),
+        m_isInitialized(false),
         m_realQZ()
     {}
 
@@ -134,8 +134,8 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       : m_eivec(size, size),
         m_alphas(size),
         m_betas(size),
-        m_valuesOkay(false),
+        m_computeEigenvectors(false),
-        m_vectorsOkay(false),
+        m_isInitialized(false),
         m_realQZ(size),
         m_tmp(size)
     {}
@@ -156,8 +156,8 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       : m_eivec(A.rows(), A.cols()),
         m_alphas(A.cols()),
         m_betas(A.cols()),
-        m_valuesOkay(false),
+        m_computeEigenvectors(false),
-        m_vectorsOkay(false),
+        m_isInitialized(false),
         m_realQZ(A.cols()),
         m_tmp(A.cols())
     {
@@ -177,7 +177,8 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       * \sa eigenvalues()
       */
     EigenvectorsType eigenvectors() const {
-      eigen_assert(m_vectorsOkay && "Eigenvectors for GeneralizedEigenSolver were not calculated.");
+      eigen_assert(info() == Success && "GeneralizedEigenSolver failed to compute eigenvectors")
+      eigen_assert(m_computeEigenvectors && "Eigenvectors for GeneralizedEigenSolver were not calculated");
       return m_eivec;
     }
 
@@ -201,7 +202,7 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       */
     EigenvalueType eigenvalues() const
     {
-      eigen_assert(m_valuesOkay && "GeneralizedEigenSolver is not initialized.");
+      eigen_assert(info() == Success && "GeneralizedEigenSolver failed to compute eigenvalues.");
       return EigenvalueType(m_alphas,m_betas);
     }
 
@@ -212,7 +213,7 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       * \sa betas(), eigenvalues() */
     ComplexVectorType alphas() const
     {
-      eigen_assert(m_valuesOkay && "GeneralizedEigenSolver is not initialized.");
+      eigen_assert(info() == Success && "GeneralizedEigenSolver failed to compute alphas.");
       return m_alphas;
     }
 
@@ -223,7 +224,7 @@ template<typename _MatrixType> class GeneralizedEigenSolver
       * \sa alphas(), eigenvalues() */
     VectorType betas() const
     {
-      eigen_assert(m_valuesOkay && "GeneralizedEigenSolver is not initialized.");
+      eigen_assert(info() == Success && "GeneralizedEigenSolver failed to compute betas.");
       return m_betas;
     }
 
@@ -254,7 +255,7 @@ template<typename _MatrixType> class GeneralizedEigenSolver
 
     ComputationInfo info() const
     {
-      eigen_assert(m_valuesOkay && "EigenSolver is not initialized.");
+      eigen_assert(m_isInitialized && "EigenSolver is not initialized.");
       return m_realQZ.info();
     }
 
@@ -277,7 +278,8 @@ template<typename _MatrixType> class GeneralizedEigenSolver
     EigenvectorsType m_eivec;
     ComplexVectorType m_alphas;
     VectorType m_betas;
-    bool m_valuesOkay, m_vectorsOkay;
+    bool m_computeEigenvectors;
+    bool m_isInitialized;
     RealQZ<MatrixType> m_realQZ;
     ComplexVectorType m_tmp;
 };
@@ -292,8 +294,6 @@ GeneralizedEigenSolver<MatrixType>::compute(const MatrixType& A, const MatrixTyp
   using std::abs;
   eigen_assert(A.cols() == A.rows() && B.cols() == A.rows() && B.cols() == B.rows());
   Index size = A.cols();
-  m_valuesOkay = false;
-  m_vectorsOkay = false;
   // Reduce to generalized real Schur form:
   // A = Q S Z and B = Q T Z
   m_realQZ.compute(A, B, computeEigenvectors);
@@ -406,10 +406,9 @@ GeneralizedEigenSolver<MatrixType>::compute(const MatrixType& A, const MatrixTyp
         i += 2;
       }
     }
-
-    m_valuesOkay = true;
-    m_vectorsOkay = computeEigenvectors;
   }
+  m_computeEigenvectors = computeEigenvectors;
+  m_isInitialized = true;
   return *this;
 }
 

test/eigensolver_generalized_real.cpp

@@ -85,6 +85,42 @@ template<typename MatrixType> void generalized_eigensolver_real(const MatrixType
   }
 }
 
+template<typename MatrixType>
+void generalized_eigensolver_assert() {
+    GeneralizedEigenSolver<MatrixType> eig;
+    // all raise assert if uninitialized
+    VERIFY_RAISES_ASSERT(eig.info());
+    VERIFY_RAISES_ASSERT(eig.eigenvectors());
+    VERIFY_RAISES_ASSERT(eig.eigenvalues());
+    VERIFY_RAISES_ASSERT(eig.alphas());
+    VERIFY_RAISES_ASSERT(eig.betas());
+
+    // none raise assert after compute called
+    eig.compute(MatrixType::Random(20, 20), MatrixType::Random(20, 20));
+    VERIFY(eig.info() == Success);
+    eig.eigenvectors();
+    eig.eigenvalues();
+    eig.alphas();
+    eig.betas();
+
+    // eigenvectors() raises assert, if eigenvectors were not requested
+    eig.compute(MatrixType::Random(20, 20), MatrixType::Random(20, 20), false);
+    VERIFY(eig.info() == Success);
+    VERIFY_RAISES_ASSERT(eig.eigenvectors());
+    eig.eigenvalues();
+    eig.alphas();
+    eig.betas();
+
+    // all except info raise assert if realQZ did not converge
+    eig.setMaxIterations(0); // force real QZ to fail.
+    eig.compute(MatrixType::Random(20, 20), MatrixType::Random(20, 20));
+    VERIFY(eig.info() == NoConvergence);
+    VERIFY_RAISES_ASSERT(eig.eigenvectors());
+    VERIFY_RAISES_ASSERT(eig.eigenvalues());
+    VERIFY_RAISES_ASSERT(eig.alphas());
+    VERIFY_RAISES_ASSERT(eig.betas());
+}
+
 EIGEN_DECLARE_TEST(eigensolver_generalized_real)
 {
   for(int i = 0; i < g_repeat; i++) {
@@ -98,6 +134,7 @@ EIGEN_DECLARE_TEST(eigensolver_generalized_real)
     CALL_SUBTEST_2( generalized_eigensolver_real(MatrixXd(2,2)) );
     CALL_SUBTEST_3( generalized_eigensolver_real(Matrix<double,1,1>()) );
     CALL_SUBTEST_4( generalized_eigensolver_real(Matrix2d()) );
+    CALL_SUBTEST_5( generalized_eigensolver_assert<MatrixXd>() );
     TEST_SET_BUT_UNUSED_VARIABLE(s)
   }
 }