From 8b43dbd9ad408fa4a17e02b6e5e1e400796b64d4 Mon Sep 17 00:00:00 2001
From: "denis.davydov" <denis.davydov@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Wed, 21 May 2014 19:04:18 +0000
Subject: [PATCH] updated operator * (VectorBase), its description and the
 corresponding test

git-svn-id: https://svn.dealii.org/branches/branch_petscscalar_complex@32959 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/include/deal.II/lac/petsc_vector_base.h | 3 +++
 deal.II/source/lac/petsc_vector_base.cc         | 6 +++++-
 tests/petsc_complex/20.cc                       | 2 +-
 tests/petsc_complex/20.output                   | 2 ++
 4 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/deal.II/include/deal.II/lac/petsc_vector_base.h b/deal.II/include/deal.II/lac/petsc_vector_base.h
index b8195d78ea..d19932da4e 100644
--- a/deal.II/include/deal.II/lac/petsc_vector_base.h
+++ b/deal.II/include/deal.II/lac/petsc_vector_base.h
@@ -544,6 +544,9 @@ namespace PETScWrappers
      * Return the scalar product of two
      * vectors. The vectors must have the
      * same size.
+     *
+     * For complex valued vector, this gives
+     * $\left(v^\ast,vec\right)$.
      */
     PetscScalar operator * (const VectorBase &vec) const;
 
diff --git a/deal.II/source/lac/petsc_vector_base.cc b/deal.II/source/lac/petsc_vector_base.cc
index 3233797c69..e441b03e64 100644
--- a/deal.II/source/lac/petsc_vector_base.cc
+++ b/deal.II/source/lac/petsc_vector_base.cc
@@ -357,7 +357,11 @@ namespace PETScWrappers
 
     PetscScalar result;
 
-    const int ierr = VecDot (vector, vec.vector, &result);
+    //For complex vectors, VecDot() computes
+    //    val = (x,y) = y^H x,
+    //where y^H denotes the conjugate transpose of y.
+    //Note that this corresponds to the usual "mathematicians" complex inner product where the SECOND argument gets the complex conjugate.
+    const int ierr = VecDot (vec.vector, vector, &result);
     AssertThrow (ierr == 0, ExcPETScError(ierr));
 
     return result;
diff --git a/tests/petsc_complex/20.cc b/tests/petsc_complex/20.cc
index f983727ff4..0774b2cef2 100644
--- a/tests/petsc_complex/20.cc
+++ b/tests/petsc_complex/20.cc
@@ -41,7 +41,7 @@ void test (PETScWrappers::Vector &v,
         {
           const PetscScalar wi = std::complex<double> (5.0-i,2.5*(i%6));
           w(i) = wi;
-          product += vi*wi;
+          product += PetscConj(vi)*wi;
         }
     }
 
diff --git a/tests/petsc_complex/20.output b/tests/petsc_complex/20.output
index e69de29bb2..0fd8fc12f0 100644
--- a/tests/petsc_complex/20.output
+++ b/tests/petsc_complex/20.output
@@ -0,0 +1,2 @@
+
+DEAL::OK
-- 
2.39.5