From acb0850361f28172441d92e726b27858b5b371bc Mon Sep 17 00:00:00 2001
From: Daniel Arndt <daniel.arndt@iwr.uni-heidelberg.de>
Date: Tue, 5 Jul 2016 17:31:37 +0200
Subject: [PATCH] Use consistent order of arguments for PETScMatrix::add

---
 include/deal.II/lac/petsc_matrix_base.h | 12 +++++++++++-
 source/lac/petsc_matrix_base.cc         | 13 +++++++++++--
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/include/deal.II/lac/petsc_matrix_base.h b/include/deal.II/lac/petsc_matrix_base.h
index 51bcad37d0..acca524ec2 100644
--- a/include/deal.II/lac/petsc_matrix_base.h
+++ b/include/deal.II/lac/petsc_matrix_base.h
@@ -701,12 +701,22 @@ namespace PETScWrappers
      */
     MatrixBase &operator /= (const PetscScalar factor);
 
+
+    /**
+     * Add the matrix @p other scaled by the factor @p factor to the current
+     * matrix.
+     */
+    MatrixBase &add (const PetscScalar factor,
+                     const MatrixBase &other);
+
+
     /**
      * Add the matrix @p other scaled by the factor @p factor to the current
      * matrix.
+     * @deprecated Use the function with order of arguments reversed instead.
      */
     MatrixBase &add (const MatrixBase &other,
-                     const PetscScalar factor);
+                     const PetscScalar factor) DEAL_II_DEPRECATED;
 
     /**
      * Matrix-vector multiplication: let <i>dst = M*src</i> with <i>M</i>
diff --git a/source/lac/petsc_matrix_base.cc b/source/lac/petsc_matrix_base.cc
index cea675dfb9..941370e3bc 100644
--- a/source/lac/petsc_matrix_base.cc
+++ b/source/lac/petsc_matrix_base.cc
@@ -470,8 +470,8 @@ namespace PETScWrappers
 
 
   MatrixBase &
-  MatrixBase::add (const MatrixBase &other,
-                   const PetscScalar factor)
+  MatrixBase::add (const PetscScalar factor,
+                   const MatrixBase &other)
   {
     const int ierr = MatAXPY (matrix, factor,
                               other, DIFFERENT_NONZERO_PATTERN);
@@ -483,6 +483,15 @@ namespace PETScWrappers
   }
 
 
+
+  MatrixBase &
+  MatrixBase::add (const MatrixBase &other,
+                   const PetscScalar factor)
+  {
+    return add(factor, other);
+  }
+
+
   void
   MatrixBase::vmult (VectorBase       &dst,
                      const VectorBase &src) const
-- 
2.39.5