Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

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Function all_gather

boost::mpi::all_gather — Gather the values stored at every process into vectors of values from each process.

Synopsis

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


template<typename T> 
  void all_gather(const communicator & comm, const T & in_value, 
                  std::vector< T > & out_values);
template<typename T> 
  void all_gather(const communicator & comm, const T & in_value, 
                  T * out_values);
template<typename T> 
  void all_gather(const communicator & comm, const T * in_values, int n, 
                  std::vector< T > & out_values);
template<typename T> 
  void all_gather(const communicator & comm, const T * in_values, int n, 
                  T * out_values);

Description

all_gather is a collective algorithm that collects the values stored at each process into a vector of values indexed by the process number they came from. The type T of the values may be any type that is serializable or has an associated MPI data type.

When the type T has an associated MPI data type, this routine invokes MPI_Allgather to gather the values.

Parameters:

`comm`	The communicator over which the all-gather will occur.
`in_value`	The value to be transmitted by each process. To gather an array of values, `in_values` points to the `n` local values to be transmitted.
`out_values`	A vector or pointer to storage that will be populated with the values from each process, indexed by the process ID number. If it is a vector, the vector will be resized accordingly.