Function gatherv

boost::mpi::gatherv — Similar to boost::mpi::gather with the difference that the number of values to be send by non-root processes can vary.

Synopsis

// In header: <boost/mpi/collectives.hpp>


template<typename T> 
  void gatherv(const communicator & comm, const std::vector< T > & in_values, 
               T * out_values, const std::vector< int > & sizes, 
               const std::vector< int > & displs, int root);
template<typename T> 
  void gatherv(const communicator & comm, const T * in_values, int in_size, 
               T * out_values, const std::vector< int > & sizes, 
               const std::vector< int > & displs, int root);
template<typename T> 
  void gatherv(const communicator & comm, const std::vector< T > & in_values, 
               int root);
template<typename T> 
  void gatherv(const communicator & comm, const T * in_values, int in_size, 
               int root);
template<typename T> 
  void gatherv(const communicator & comm, const T * in_values, int in_size, 
               T * out_values, const std::vector< int > & sizes, int root);
template<typename T> 
  void gatherv(const communicator & comm, const std::vector< T > & in_values, 
               T * out_values, const std::vector< int > & sizes, int root);

Description

Parameters:

`comm`	The communicator over which the gather will occur.
`displs`	A vector such that the i-th entry specifies the displacement (relative to `out_values`) from which to take the ingoing data at the `root` process. Overloaded versions for which `displs` is omitted assume that the data is to be placed contiguously at the root process.
`in_values`	The array of values to be transmitted by each process.
`out_values`	A pointer to storage that will be populated with the values from each process. For non-root processes, this parameter may be omitted. If it is still provided, however, it will be unchanged.
`root`	The process ID number that will collect the values. This value must be the same on all processes.
`sizes`	A vector containing the number of elements each non-root process will send.