Ifpack2 Templated Preconditioning Package Version 1.0
Ifpack2_LinearPartitioner_def.hpp
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00004 //       Ifpack2: Tempated Object-Oriented Algebraic Preconditioner Package
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00042
00043 #ifndef IFPACK2_LINEAR_PARTITIONER_DEF_HPP
00044 #define IFPACK2_LINEAR_PARTITIONER_DEF_HPP
00045 #include "Ifpack2_ConfigDefs.hpp"
00046 #include "Ifpack2_LinearPartitioner_decl.hpp"
00047
00048 namespace Ifpack2 {
00049
00050 //==============================================================================
00051 // Constructor
00052 template<class GraphType>
00053 LinearPartitioner<GraphType>::
00054 LinearPartitioner (const Teuchos::RCP<const row_graph_type>& graph) :
00055   OverlappingPartitioner<GraphType> (graph)
00056 {}
00057
00058
00059 template<class GraphType>
00060 LinearPartitioner<GraphType>::~LinearPartitioner() {}
00061
00062
00063 template<class GraphType>
00064 void
00065 LinearPartitioner<GraphType>::
00066 setPartitionParameters (Teuchos::ParameterList& List) {}
00067
00068
00069 template<class GraphType>
00070 void LinearPartitioner<GraphType>::LinearPartitioner::computePartitions()
00071 {
00072   using Teuchos::as;
00073   // Partition_ is an array of local_ordinal_type.  local_ordinal_type
00074   // may be signed or unsigned.  NumLocalParts_ is int, and needs to
00075   // be signed, since negative values are significant.  Comparisons
00076   // between signed and unsigned integers often result in compiler
00077   // warnings, which is why we use as() for explicit conversions
00078   // below.  We also use as() because in a debug build, it checks for
00079   // overflow.
00080   const int mod = as<int> (this->Graph_->getNodeNumRows () /
00081          this->NumLocalParts_);
00082   for (size_t i = 0; i < this->Graph_->getNodeNumRows (); ++i) {
00083     this->Partition_[i] = as<local_ordinal_type> (i / mod);
00084     if (this->Partition_[i] >= as<local_ordinal_type> (this->NumLocalParts_)) {
00085       this->Partition_[i] = this->NumLocalParts_ - 1;
00086     }
00087   }
00088 }
00089
00090
00091 }// namespace Ifpack2
00092
00093 #endif // IFPACK2_LINEARPARTITIONER_DEF_HPP
00094