Avoid calls to naked compress() without a VectorOperation argument.

diff --git a/tests/trilinos/01.cc b/tests/trilinos/01.cc
index bc4ac477e16e7444424a748ea8fde5bc4da7c710..f2692c7c95eb1afbb3d60926ef9374bf2cf24c16 100644 (file)
--- a/tests/trilinos/01.cc
+++ b/tests/trilinos/01.cc
@@ -33,7 +33,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // then make sure we retrieve the same ones
   for (unsigned int i=0; i<m.m(); ++i)

diff --git a/tests/trilinos/02.cc b/tests/trilinos/02.cc
index e4f149b9eb0a264696604074ba58d0df84bbf715..b655f8792000d32b0b91562a3e9072edc0362532 100644 (file)
--- a/tests/trilinos/02.cc
+++ b/tests/trilinos/02.cc
@@ -39,7 +39,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.add (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::add);
 
   // then make sure we retrieve the same ones
   for (unsigned int i=0; i<m.m(); ++i)

diff --git a/tests/trilinos/03a.cc b/tests/trilinos/03a.cc
index fc9c066cec8338b11b4cc4e98bf08709ac076623..2fb3c42312419d77e9643056d204e4be44f7b62a 100644 (file)
--- a/tests/trilinos/03a.cc
+++ b/tests/trilinos/03a.cc
@@ -43,7 +43,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.add (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::add);
 
   // then make sure we retrieve the same ones
   for (unsigned int i=0; i<m.m(); ++i)

diff --git a/tests/trilinos/03b.cc b/tests/trilinos/03b.cc
index 89072fc0ee7e143e8ed6c2f4b78661ecb62ef605..cdb74ea0a96ea034fc67ff9df486e4ae25c93879 100644 (file)
--- a/tests/trilinos/03b.cc
+++ b/tests/trilinos/03b.cc
@@ -42,7 +42,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.add (i,j, i*j*.5+.5);
 
-  m.compress();
+  m.compress(VectorOperation::add);
 
   // and overwrite everything again
   for (unsigned int i=0; i<m.m(); ++i)
@@ -50,7 +50,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // then make sure we retrieve the same ones
   for (unsigned int i=0; i<m.m(); ++i)

diff --git a/tests/trilinos/05.cc b/tests/trilinos/05.cc
index 52345a66fa2a8cf750b1253b7b876bd28938c498..5e43cf4425a3881b5e8cde926df3f8f9086b0149 100644 (file)
--- a/tests/trilinos/05.cc
+++ b/tests/trilinos/05.cc
@@ -38,7 +38,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
           ++counter;
         }
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   deallog << m.n_nonzero_elements() << std::endl;
   Assert (m.n_nonzero_elements() == counter,

diff --git a/tests/trilinos/06.cc b/tests/trilinos/06.cc
index bb39bb4f5d14bc5b63f850339af0b51e9f32f023..153915371174e620643a9dbeb9ba4662945a0da1 100644 (file)
--- a/tests/trilinos/06.cc
+++ b/tests/trilinos/06.cc
@@ -33,7 +33,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // compare against the exact value of the
   // l1-norm (max col-sum)

diff --git a/tests/trilinos/07.cc b/tests/trilinos/07.cc
index 4aeb526b6a3341005e676c761094340e669b28f6..051f8456eddcd2901f72214f0283215cfa7d67e8 100644 (file)
--- a/tests/trilinos/07.cc
+++ b/tests/trilinos/07.cc
@@ -33,7 +33,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // compare against the exact value of the
   // linfty-norm (max row-sum)

diff --git a/tests/trilinos/08.cc b/tests/trilinos/08.cc
index 36fbcf8e41383cff8dd3d1746b5d302c82948ed8..ede3154347915d119f5d6869b642d192a8a7b0cd 100644 (file)
--- a/tests/trilinos/08.cc
+++ b/tests/trilinos/08.cc
@@ -38,7 +38,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
         }
   norm = std::sqrt(norm);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // compare against the exact value of the
   // l2-norm (max row-sum)

diff --git a/tests/trilinos/09.cc b/tests/trilinos/09.cc
index 37090475f8547a9ddfb722d4d0660dbaf1a1f819..17c49050546c0253e93c45651e6aa697fc8c93d2 100644 (file)
--- a/tests/trilinos/09.cc
+++ b/tests/trilinos/09.cc
@@ -32,7 +32,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // then multiply everything by 1.25 and
   // make sure we retrieve the values we

diff --git a/tests/trilinos/10.cc b/tests/trilinos/10.cc
index 4dc8a0fa85164e15a5c80f5a970337aa54c837f7..5f1eaef2744e71af190f38cf588f5456d58ec4d6 100644 (file)
--- a/tests/trilinos/10.cc
+++ b/tests/trilinos/10.cc
@@ -32,7 +32,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // then divide everything by 4/3 and
   // make sure we retrieve the values we

diff --git a/tests/trilinos/52.cc b/tests/trilinos/52.cc
index 5b105b0f39145edefd94631b061d60df725ba84c..40c7a4b1bf6020cb0441f02c9ea862f0f4588a95 100644 (file)
--- a/tests/trilinos/52.cc
+++ b/tests/trilinos/52.cc
@@ -34,7 +34,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   // then make sure we retrieve the same ones
   for (unsigned int i=0; i<m.m(); ++i)

diff --git a/tests/trilinos/64.cc b/tests/trilinos/64.cc
index 9ccd8f2ba5475aaa645e82ac3b208a6a4873372c..fca507bfd3a16bcf55ec23f1451d1ac2d2f288a4 100644 (file)
--- a/tests/trilinos/64.cc
+++ b/tests/trilinos/64.cc
@@ -34,9 +34,9 @@ template<typename MatrixType>
 void test (MatrixType &m)
 {
   m.set(0,0,1.);
-  m.compress();
+  m.compress(VectorOperation::insert);
   m = 0;
-  m.compress();
+  m.compress(VectorOperation::insert);
 
   Assert(fabs(m.frobenius_norm())<1e-15, ExcInternalError());
 

diff --git a/tests/trilinos/add_matrices_06.cc b/tests/trilinos/add_matrices_06.cc
index 93ed824bd3472d3fb27d1e632996b1df141dd95b..7e16b9bc7963f389915c259a6cc543a3d27d2f26 100644 (file)
--- a/tests/trilinos/add_matrices_06.cc
+++ b/tests/trilinos/add_matrices_06.cc
@@ -42,9 +42,9 @@ void test (TrilinosWrappers::SparseMatrix &m)
           m3.set (i,j, -0.1);
         }
 
-  m.compress ();
-  m2.compress();
-  m3.compress();
+  m.compress (VectorOperation::insert);
+  m2.compress(VectorOperation::insert);
+  m3.compress(VectorOperation::insert);
 
   deallog << "Matrix nonzeros: " << m.n_nonzero_elements() <<  " "
           << m2.n_nonzero_elements() <<  " "

diff --git a/tests/trilinos/block_sparse_matrix_add_01.cc b/tests/trilinos/block_sparse_matrix_add_01.cc
index 8bd7aac4dc04aaa2d146cde215cacd2ba43ad9d5..5f3a33422cde54f9303d6bcc0984242348564ab6 100644 (file)
--- a/tests/trilinos/block_sparse_matrix_add_01.cc
+++ b/tests/trilinos/block_sparse_matrix_add_01.cc
@@ -50,7 +50,7 @@ void test ()
 
           m_small.set (i,j, value);
         }
-  m_small.compress();
+  m_small.compress(VectorOperation::insert);
 
   // Then build two matrices consisting of
   // several copies of the small
@@ -105,7 +105,7 @@ void test ()
       }
   }
 
-  m2.compress();
+  m2.compress(VectorOperation::add);
 
   // subtract the matrix m from this one,
   // we should get a zero matrix

diff --git a/tests/trilinos/block_sparse_matrix_set_01.cc b/tests/trilinos/block_sparse_matrix_set_01.cc
index 68097c2f32895bddd4595baaad4488f7b5ce4e26..ea13559af1b55ea315285f3dd93559e47f11ce95 100644 (file)
--- a/tests/trilinos/block_sparse_matrix_set_01.cc
+++ b/tests/trilinos/block_sparse_matrix_set_01.cc
@@ -51,7 +51,7 @@ void test ()
 
           m_small.set (i,j, value);
         }
-  m_small.compress();
+  m_small.compress(VectorOperation::insert);
 
   // Then build two matrices consisting of
   // several copies of the small
@@ -106,7 +106,7 @@ void test ()
       }
   }
 
-  m2.compress();
+  m2.compress(VectorOperation::insert);
 
   // subtract the matrix m from this one,
   // we should get a zero matrix

diff --git a/tests/trilinos/deal_solver_01.cc b/tests/trilinos/deal_solver_01.cc
index 14c36b4b7c093e5ea37d23a06a05704c2da33501..495b362bdc46ec8770c0e4a87c1724c373cb95d5 100644 (file)
--- a/tests/trilinos/deal_solver_01.cc
+++ b/tests/trilinos/deal_solver_01.cc
@@ -93,7 +93,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/deal_solver_02.cc b/tests/trilinos/deal_solver_02.cc
index 21b3c5d5ea52a26d72fab417b5e8751e04cda83c..c9ce6575575a996f7fe47283cc268006d742cefc 100644 (file)
--- a/tests/trilinos/deal_solver_02.cc
+++ b/tests/trilinos/deal_solver_02.cc
@@ -94,7 +94,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/deal_solver_03.cc b/tests/trilinos/deal_solver_03.cc
index 394a9489f290c47cf6193b6952561ce3f22a9626..031d63da4501eff4bce160d180a699210917f24a 100644 (file)
--- a/tests/trilinos/deal_solver_03.cc
+++ b/tests/trilinos/deal_solver_03.cc
@@ -95,7 +95,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/deal_solver_04.cc b/tests/trilinos/deal_solver_04.cc
index 87ee0046936b172a9b2e26634cd18ba6e59f7be9..acb9625aa01d755ce33633430cb1efa57d861ad3 100644 (file)
--- a/tests/trilinos/deal_solver_04.cc
+++ b/tests/trilinos/deal_solver_04.cc
@@ -94,7 +94,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/deal_solver_05.cc b/tests/trilinos/deal_solver_05.cc
index a34b93bf98cc11584057e7bdfd5925d1b45d7c63..902311ecc07432993ef71ee10f6236b3b2929a29 100644 (file)
--- a/tests/trilinos/deal_solver_05.cc
+++ b/tests/trilinos/deal_solver_05.cc
@@ -93,7 +93,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/deal_solver_06.cc b/tests/trilinos/deal_solver_06.cc
index 312b6bc111be37da892184aa37a5b39ea5188631..502361e1baa20565aa98374bb56f9e9a22f64960 100644 (file)
--- a/tests/trilinos/deal_solver_06.cc
+++ b/tests/trilinos/deal_solver_06.cc
@@ -91,7 +91,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/parallel_sparse_matrix_01.cc b/tests/trilinos/parallel_sparse_matrix_01.cc
index 5937d8c726a651d1f5472ca3f9be5fb70ffc3170..d7b03b6bd59188865318db3d1782e8b33b1748e3 100644 (file)
--- a/tests/trilinos/parallel_sparse_matrix_01.cc
+++ b/tests/trilinos/parallel_sparse_matrix_01.cc
@@ -97,7 +97,7 @@ void test ()
     for (unsigned int j=0; j<csp.row_length(i); ++j)
       m.add (i, csp.column_number(i,j), 1.);
 
-  m.compress ();
+  m.compress (VectorOperation::add);
 
   deallog << "OK" << std::endl;
 }

diff --git a/tests/trilinos/slowness_02.cc b/tests/trilinos/slowness_02.cc
index 7efba915c05878bf46e1ee3163d72eb0f4b87822..01ef33212585e046546e96a4890f8d933bc9ee65 100644 (file)
--- a/tests/trilinos/slowness_02.cc
+++ b/tests/trilinos/slowness_02.cc
@@ -63,7 +63,7 @@ void test ()
             matrix.set(global, global+N, -1);
           }
       }
-  matrix.compress ();
+  matrix.compress (VectorOperation::insert);
 
 
   // then do a single matrix-vector

diff --git a/tests/trilinos/slowness_03.cc b/tests/trilinos/slowness_03.cc
index 6afbf1ce3766b5bb16adda9f5a9ee5e77a90e9ce..ebe2d928c821c9f062ce19cdd8de7f4eab6d656b 100644 (file)
--- a/tests/trilinos/slowness_03.cc
+++ b/tests/trilinos/slowness_03.cc
@@ -65,7 +65,7 @@ void test ()
             matrix.set(global, global+N, -1);
           }
       }
-  matrix.compress ();
+  matrix.compress (VectorOperation::insert);
 
   // then do a single matrix-vector
   // multiplication with subsequent formation

diff --git a/tests/trilinos/solver_03.cc b/tests/trilinos/solver_03.cc
index d73e57fccab86eb3a96ee7069ef29cbf85812861..f2c200429871e4b7cd1a2bf06858b08035a954d5 100644 (file)
--- a/tests/trilinos/solver_03.cc
+++ b/tests/trilinos/solver_03.cc
@@ -88,7 +88,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/solver_05.cc b/tests/trilinos/solver_05.cc
index b47004759b93d340314f83299f9e612b285afbca..4c9e437907dfa05d3c6cf61ddbbfbab067ffc1bb 100644 (file)
--- a/tests/trilinos/solver_05.cc
+++ b/tests/trilinos/solver_05.cc
@@ -88,7 +88,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/solver_07.cc b/tests/trilinos/solver_07.cc
index 7a746bc0160aa5bf4f4a71bd61e5402974ed5f2f..2aad2f3e5d9044c07bdfa78da6c101463a591e2f 100644 (file)
--- a/tests/trilinos/solver_07.cc
+++ b/tests/trilinos/solver_07.cc
@@ -87,7 +87,7 @@ int main(int argc, char **argv)
     TrilinosWrappers::Vector  f(dim);
     TrilinosWrappers::Vector  u(dim);
     f = 1.;
-    A.compress ();
+    A.compress (VectorOperation::insert);
     f.compress (VectorOperation::insert);
     u.compress (VectorOperation::insert);
 

diff --git a/tests/trilinos/sparse_matrix_01.cc b/tests/trilinos/sparse_matrix_01.cc
index d11293884aac5c040d45a2cde44d6514e75a4ba9..9d5ff4d9fc0e29114c67d8ab715ab1ebafe0430c 100644 (file)
--- a/tests/trilinos/sparse_matrix_01.cc
+++ b/tests/trilinos/sparse_matrix_01.cc
@@ -52,7 +52,7 @@ int main (int argc,char **argv)
 
   TrilinosWrappers::SparseMatrix A (sp);
   A.add (2, 3, 2.0);
-  A.compress();
+  A.compress(VectorOperation::add);
 
   // verify that entry (2,3) is
   // indeed what we expect. verify

diff --git a/tests/trilinos/sparse_matrix_add_01.cc b/tests/trilinos/sparse_matrix_add_01.cc
index 273ccf4b7c7b224fbfdb5ecf05a5566edcfbe6f8..06cdf2145769309b30ef788dd360a647dc039a7d 100644 (file)
--- a/tests/trilinos/sparse_matrix_add_01.cc
+++ b/tests/trilinos/sparse_matrix_add_01.cc
@@ -38,8 +38,8 @@ void test (TrilinosWrappers::SparseMatrix &m)
           m2.set (i,j, 0.);
         }
 
-  m.compress ();
-  m2.compress();
+  m.compress (VectorOperation::insert);
+  m2.compress(VectorOperation::insert);
 
   // now add the same elements row-wise
   {
@@ -71,7 +71,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       }
   }
 
-  m2.compress();
+  m2.compress(VectorOperation::add);
 
   // subtract the matrix m from this one,
   // we should get a zero matrix

diff --git a/tests/trilinos/sparse_matrix_add_02.cc b/tests/trilinos/sparse_matrix_add_02.cc
index dd559cb089bc8a21041c93340858e8d43b266d83..90a738b1b62f14b3d1df698cf1f00b529c2a59b1 100644 (file)
--- a/tests/trilinos/sparse_matrix_add_02.cc
+++ b/tests/trilinos/sparse_matrix_add_02.cc
@@ -51,8 +51,8 @@ void test (TrilinosWrappers::SparseMatrix &m)
           m2.set (i,j, 0.);
         }
 
-  m.compress ();
-  m2.compress();
+  m.compress (VectorOperation::insert);
+  m2.compress(VectorOperation::insert);
 
   // now add the same elements from a full
   // matrix
@@ -71,7 +71,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       }
   }
 
-  m2.compress();
+  m2.compress(VectorOperation::add);
 
   // subtract the matrix m from this one,
   // we should get a zero matrix

diff --git a/tests/trilinos/sparse_matrix_iterator_01.cc b/tests/trilinos/sparse_matrix_iterator_01.cc
index 1bb0902439db489b8874f8bdd9bf69e9fc24d095..2eb1d628de5da76abeb2799e20ffb72807356acf 100644 (file)
--- a/tests/trilinos/sparse_matrix_iterator_01.cc
+++ b/tests/trilinos/sparse_matrix_iterator_01.cc
@@ -30,7 +30,7 @@ void test ()
   m.set (0,0,1);
   m.set (1,1,2);
   m.set (1,2,3);
-  m.compress ();
+  m.compress (VectorOperation::insert);
   TrilinosWrappers::SparseMatrix::const_iterator i = m.begin();
   deallog << i->row() << ' ' << i->column() << ' ' << i->value() << std::endl;
   ++i;

diff --git a/tests/trilinos/sparse_matrix_set_01.cc b/tests/trilinos/sparse_matrix_set_01.cc
index 039e3029086b4b4223ae757d97a3f09b27215467..8824c123330d566650fafb61e77b56d7f79f6fc5 100644 (file)
--- a/tests/trilinos/sparse_matrix_set_01.cc
+++ b/tests/trilinos/sparse_matrix_set_01.cc
@@ -33,7 +33,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       if ((i+2*j+1) % 3 == 0)
         m.set (i,j, i*j*.5+.5);
 
-  m.compress ();
+  m.compress (VectorOperation::insert);
 
   TrilinosWrappers::SparseMatrix m2(m.m(), m.n(), m.n()/3+1);
 
@@ -67,7 +67,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       }
   }
 
-  m2.compress();
+  m2.compress(VectorOperation::insert);
 
   // subtract the matrix m from this one,
   // we should get a zero matrix.

diff --git a/tests/trilinos/sparse_matrix_set_02.cc b/tests/trilinos/sparse_matrix_set_02.cc
index 49254ee693088704c8923e5f64c50a0c9c83b157..c0146fa529d4192c0579dfa8363b292db35eaa3f 100644 (file)
--- a/tests/trilinos/sparse_matrix_set_02.cc
+++ b/tests/trilinos/sparse_matrix_set_02.cc
@@ -49,7 +49,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
 
           m.set (i,j, value);
         }
-  m.compress ();
+  m.compress (VectorOperation::insert);
   // now add the same elements from a full
   // matrix (if the same element is set
   // more than once, Trilinos adds them)
@@ -68,7 +68,7 @@ void test (TrilinosWrappers::SparseMatrix &m)
       }
   }
 
-  m2.compress();
+  m2.compress(VectorOperation::insert);
 
   // subtract the matrix m from this one,
   // we should get a zero matrix