The simplest datatype constructor is MPI_TYPE_CONTIGUOUS which allows replication of a datatype into contiguous locations.
MPI_TYPE_CONTIGUOUS(count, oldtype, newtype)
int MPI_Type_contiguous(int count, MPI_Datatype oldtype, MPI_Datatype *newtype)
MPI_TYPE_CONTIGUOUS(COUNT, OLDTYPE, NEWTYPE, IERROR)
INTEGER COUNT, OLDTYPE, NEWTYPE, IERROR
newtype is the datatype obtained by concatenating count copies of oldtype. Concatenation is defined using extent as the size of the concatenated copies.
In general,
assume that the type map of oldtype is
MPI-Standard for MARMOT