communicator.cc
Go to the documentation of this file.
1 //LIC// ====================================================================
2 //LIC// This file forms part of oomph-lib, the object-oriented,
3 //LIC// multi-physics finite-element library, available
4 //LIC// at http://www.oomph-lib.org.
5 //LIC//
6 //LIC// Version 1.0; svn revision $LastChangedRevision$
7 //LIC//
8 //LIC// $LastChangedDate$
9 //LIC//
10 //LIC// Copyright (C) 2006-2016 Matthias Heil and Andrew Hazel
11 //LIC//
12 //LIC// This library is free software; you can redistribute it and/or
13 //LIC// modify it under the terms of the GNU Lesser General Public
14 //LIC// License as published by the Free Software Foundation; either
15 //LIC// version 2.1 of the License, or (at your option) any later version.
16 //LIC//
17 //LIC// This library is distributed in the hope that it will be useful,
18 //LIC// but WITHOUT ANY WARRANTY; without even the implied warranty of
19 //LIC// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 //LIC// Lesser General Public License for more details.
21 //LIC//
22 //LIC// You should have received a copy of the GNU Lesser General Public
23 //LIC// License along with this library; if not, write to the Free Software
24 //LIC// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
25 //LIC// 02110-1301 USA.
26 //LIC//
27 //LIC// The authors may be contacted at oomph-lib@maths.man.ac.uk.
28 //LIC//
29 //LIC//====================================================================
30 // Functions for OomphCommunicator
31 
32 // MPI headers
33 #ifdef OOMPH_HAS_MPI
34 #include "mpi.h"
35 #endif
36 
37 // Oomph-lib error handler
38 #include "communicator.h"
39 #include "matrices.h"
40 
41 namespace oomph{
42 
43 #ifdef OOMPH_HAS_MPI
44 
45 //=============================================================================
46 /// A broadcast function for DenseMatrix<double>
47 //=============================================================================
48  void OomphCommunicator::broadcast(const int& source, DenseMatrix<double>& x)
49  {
50  // Get number of entries on processor source (where the matrix exists)
51  unsigned nrow,ncol;
52  if (this->my_rank()==source)
53  {
54  nrow=x.nrow();
55  if(nrow>0)
56  {ncol=x.ncol();}
57  else
58  {ncol=0;}
59  }
60 
61  // Broadcast to everybody how many entries to expect
62  MPI_Bcast(&nrow,1,MPI_UNSIGNED_LONG,source,this->mpi_comm());
63  MPI_Bcast(&ncol,1,MPI_UNSIGNED_LONG,source,this->mpi_comm());
64 
65  if(ncol!=0 && nrow!=0)
66  {
67  // convert into a C-style array
68  double* x_bcast=new double[nrow*ncol];
69 
70  if(this->my_rank()==source)
71  for (unsigned long i=0;i<nrow;i++)
72  {
73  for (unsigned long j=0;j<ncol;j++)
74  {
75  x_bcast[i*ncol+j]=x(i,j);
76  }
77  }
78 
79  // broadcast the array
80  MPI_Bcast(x_bcast,ncol*nrow,MPI_DOUBLE,source,this->mpi_comm());
81 
82  // Now convert back into matrix (everywhere apart from source)
83  if (this->my_rank()!=source)
84  {
85  x.resize(nrow,ncol);
86  for (unsigned long i=0;i<nrow;i++)
87  for (unsigned long j=0;j<ncol;j++)
88  {
89  x(i,j)=x_bcast[i*ncol+j];
90  }
91  }
92  // delete C-style array
93  delete[] x_bcast;
94  }
95  else
96  {
97  x.resize(0,0);
98  }
99  }
100 
101 #endif
102 
103 } // end of oomph namespace
i
cstr elem_len * i
Definition: cfortran.h:607