+ /*!
+ \anchor ExplicitCoincidentDEC-det
+ \class ExplicitCoincidentDEC
+
+
+ This class aims at \ref interpolation "remapping fields" that have identical
+ supports (=the same underlying mesh) but different parallel topologies
+ (=different sub-domains in the mesh). It can be used to couple
+ together multi-physics codes that operate on the same domain
+ with different partitioning.
+
+ It is very similar to what the \ref StructuredCoincidentDEC-det "StructuredCoincidentDEC"
+ does, except that it works with an arbitrary user-defined topology.
+
+ The remapping between the two supports is based on identity of global
+ ids, instead of geometrical considerations (as it is the case for
+ \ref InterpKernelDEC-det "InterpKernelDEC").
+ Therefore, beware that this \ref para-dec "DEC" can not be used
+ for coincident meshes if they do *not* have the exact same numbering.
+
+ With this \ref para-dec "DEC" no projection, and no interpolation of the field data is done, contrary
+ to what happens in \ref InterpKernelDEC-det "InterpKernelDEC". It is just
+ a matter of allocating the values from one side to the other, using directly the cell
+ identifiers.
+
+ As all the other DECs, its usage requires two phases :
+ - a setup phase during which the topologies are exchanged so that
+ the target side knows from which processors it should expect
+ the data.
+ - a send/recv phase during which the field data is actually transferred.
+
+ This example illustrates the sending of a field with
+ the \c ExplicitCoincidentDEC :
+ \code
+ ...
+ ExplicitCoincidentDEC dec(groupA, groupB);
+ dec.attachLocalField(field);
+ dec.synchronize();
+ if (groupA.containsMyRank())
+ dec.recvData();
+ else if (groupB.containsMyRank())
+ dec.sendData();
+ ...
+ \endcode
+
+ Creating a ParaFIELD to be attached to the %DEC is done in exactly the same way as for
+ the other DECs, if only the partitioning of the support mesh differs.
+ In the case where the
+ fields have also different *component* topologies, creating the ParaFIELD
+ requires some more effort. See the \ref para-over "parallelism" section for more details.
+ */
+
+
+ /*! Constructor
+ */
+ ExplicitCoincidentDEC::ExplicitCoincidentDEC():
+ _toposource(0),_topotarget(0),
+ _targetgroup(0), _sourcegroup(0),
+ _sendcounts(0), _recvcounts(0),
+ _senddispls(0), _recvdispls(0),
+ _recvbuffer(0), _sendbuffer(0),
+ _distant_elems(), _explicit_mapping()