Simplify Chebyshev preconditioner setup by using signals

diff --git a/include/deal.II/lac/precondition.h b/include/deal.II/lac/precondition.h
index 3e2e003fa2a771c34b3949d88f5261018dddbe4a..313e6539efef9156f69c6a128fc232b196d76145 100644 (file)
--- a/include/deal.II/lac/precondition.h
+++ b/include/deal.II/lac/precondition.h
@@ -1398,6 +1398,17 @@ namespace internal
 
       const VECTOR &diagonal_vector;
     };
+
+    struct EigenvalueTracker
+    {
+    public:
+      void slot(const std::vector<double> &eigenvalues)
+      {
+        values = eigenvalues;
+      }
+
+      std::vector<double> values;
+    };
   }
 }
 
@@ -1459,15 +1470,6 @@ PreconditionChebyshev<MATRIX,VECTOR>::initialize (const MATRIX &matrix,
       Assert (additional_data.eig_cg_n_iterations > 2,
               ExcMessage ("Need to set at least two iterations to find eigenvalues."));
 
-      // attach stream to SolverCG, run it with log report for eigenvalues
-      std::ostream *old_stream = deallog.has_file() ? &deallog.get_file_stream() :
-                                 static_cast<std::ostream *>(0);
-      if (old_stream)
-        deallog.detach();
-
-      std::ostringstream log_msg;
-      deallog.attach(log_msg);
-
       // set a very strict tolerance to force at least two iterations
       ReductionControl control (data.eig_cg_n_iterations, 1e-20, 1e-20);
       GrowingVectorMemory<VECTOR> memory;
@@ -1477,9 +1479,11 @@ PreconditionChebyshev<MATRIX,VECTOR>::initialize (const MATRIX &matrix,
       dummy->reinit(data.matrix_diagonal_inverse);
       *rhs = 1./std::sqrt(static_cast<double>(matrix.m()));
 
-      typename SolverCG<VECTOR>::AdditionalData cg_data;
-      cg_data.compute_eigenvalues = true;
-      SolverCG<VECTOR> solver (control, memory, cg_data);
+      internal::PreconditionChebyshev::EigenvalueTracker eigenvalue_tracker;
+      SolverCG<VECTOR> solver (control, memory);
+      solver.connect_eigenvalues_slot(std_cxx11::bind(&internal::PreconditionChebyshev::EigenvalueTracker::slot,
+                                                      &eigenvalue_tracker,
+                                                      std_cxx11::_1));
       internal::PreconditionChebyshev::DiagonalPreconditioner<VECTOR>
       preconditioner(data.matrix_diagonal_inverse);
       try
@@ -1495,32 +1499,14 @@ PreconditionChebyshev<MATRIX,VECTOR>::initialize (const MATRIX &matrix,
       memory.free(dummy);
       memory.free(rhs);
 
-      // read the log stream: grab the first and last eigenvalue
-      std::string cg_message = log_msg.str();
-      const std::size_t pos = cg_message.find("cg:: ");
-      if (pos != std::string::npos)
+      // read the eigenvalues from the attached eigenvalue tracker
+      if (eigenvalue_tracker.values.empty())
+        min_eigenvalue = max_eigenvalue = 1;
+      else
         {
-          cg_message.erase(0, pos+5);
-          std::string first = cg_message;
-
-          if (cg_message.find_first_of(" ") != std::string::npos)
-            first.erase(cg_message.find_first_of(" "), std::string::npos);
-          std::istringstream(first)      >> min_eigenvalue;
-
-          if (cg_message.find_last_of(" ") != std::string::npos)
-            {
-              cg_message.erase(0, cg_message.find_last_of(" ")+1);
-              std::istringstream(cg_message) >> max_eigenvalue;
-            }
-          else max_eigenvalue = min_eigenvalue;
+          min_eigenvalue = eigenvalue_tracker.values.front();
+          max_eigenvalue = eigenvalue_tracker.values.back();
         }
-      else
-        min_eigenvalue = max_eigenvalue = 1;
-
-      // reset deal.II stream
-      deallog.detach();
-      if (old_stream)
-        deallog.attach(*old_stream);
 
       // include a safety factor since the CG method will in general not be
       // converged

diff --git a/tests/lac/precondition_chebyshev_01.with_lapack=true.output b/tests/lac/precondition_chebyshev_01.with_lapack=true.output
index eede3a88806a33c14f52a686a6b60a08d565c917..95c8d736ec1256d16451c55862a5893f3d9fda28 100644 (file)
--- a/tests/lac/precondition_chebyshev_01.with_lapack=true.output
+++ b/tests/lac/precondition_chebyshev_01.with_lapack=true.output
@@ -1,8 +1,10 @@
 
-
+DEAL:cg::Starting value 1.00
+DEAL:cg::Convergence step 2 value 0
 DEAL::Exact inverse:     0.84 0.20 0.26 0.20 0.18 0.03 0.05 0.10 0.03 0.06 
 DEAL::Check  vmult orig: 1.09 0.26 0.34 0.26 0.24 0.04 0.06 0.12 0.04 0.07 
 DEAL::Check Tvmult orig: 1.09 0.26 0.34 0.26 0.24 0.04 0.06 0.12 0.04 0.07 
-
+DEAL:cg::Starting value 1.00
+DEAL:cg::Failure step 8 value 0.00
 DEAL::Check  vmult diag: 0.82 0.26 0.33 0.21 0.15 0.02 0.03 0.09 0.03 0.07 
 DEAL::Check Tvmult diag: 0.82 0.26 0.33 0.21 0.15 0.02 0.03 0.09 0.03 0.07 

diff --git a/tests/matrix_free/step-37.with_lapack=true.output b/tests/matrix_free/step-37.with_lapack=true.output
index 6528cc9124de6e02f97758023c3568764039204d..2ef2bd9d95db6a844b6cc7129ee251b5e7441228 100644 (file)
--- a/tests/matrix_free/step-37.with_lapack=true.output
+++ b/tests/matrix_free/step-37.with_lapack=true.output
@@ -1,52 +1,73 @@
 
 DEAL:2d::Cycle 0
 DEAL:2d::Number of degrees of freedom: 81
-
-
-
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Convergence step 3 value 0
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0.00110
 DEAL:2d:cg::Starting value 0.132
 DEAL:2d:cg::Convergence step 4 value 0
 DEAL:2d::
 DEAL:2d::Cycle 1
 DEAL:2d::Number of degrees of freedom: 289
-
-
-
-
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Convergence step 3 value 0
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0.00110
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0.153
 DEAL:2d:cg::Starting value 0.0677
 DEAL:2d:cg::Convergence step 5 value 0
 DEAL:2d::
 DEAL:2d::Cycle 2
 DEAL:2d::Number of degrees of freedom: 1089
-
-
-
-
-
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Convergence step 3 value 0
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0.00110
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 0.153
+DEAL:2d:cg::Starting value 1.00
+DEAL:2d:cg::Failure step 10 value 1.07
 DEAL:2d:cg::Starting value 0.0343
 DEAL:2d:cg::Convergence step 5 value 0
 DEAL:2d::
 DEAL:3d::Cycle 0
 DEAL:3d::Number of degrees of freedom: 125
-
-
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Convergence step 3 value 0
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Failure step 10 value 0
 DEAL:3d:cg::Starting value 0.125
 DEAL:3d:cg::Convergence step 5 value 0
 DEAL:3d::
 DEAL:3d::Cycle 1
 DEAL:3d::Number of degrees of freedom: 729
-
-
-
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Convergence step 3 value 0
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Failure step 10 value 0
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Failure step 10 value 0.000695
 DEAL:3d:cg::Starting value 0.0479
 DEAL:3d:cg::Convergence step 4 value 0
 DEAL:3d::
 DEAL:3d::Cycle 2
 DEAL:3d::Number of degrees of freedom: 4913
-
-
-
-
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Convergence step 3 value 0
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Failure step 10 value 0
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Failure step 10 value 0.000695
+DEAL:3d:cg::Starting value 1.00
+DEAL:3d:cg::Failure step 10 value 0.0952
 DEAL:3d:cg::Starting value 0.0176
 DEAL:3d:cg::Convergence step 4 value 0
 DEAL:3d::