pbdMPI (version 0.5-2)

irecv-method: A Rank Receives (Nonblocking) an Object from the Other Rank

Description

This method lets a rank receive (nonblocking) an object from the other rank in the same communicator. The default return is the object sent from the other rank.

Usage

irecv(x.buffer = NULL, rank.source = .pbd_env$SPMD.CT$rank.source,
      tag = .pbd_env$SPMD.CT$tag, comm = .pbd_env$SPMD.CT$comm,
      request = .pbd_env$SPMD.CT$request,
      status = .pbd_env$SPMD.CT$status)

Value

An object is returned by default.

Arguments

x.buffer

a buffer to store x sent from the other rank.

rank.source

a source rank where x sent from

tag

a tag number.

comm

a communicator number.

request

a request number.

status

a status number.

Methods

For calling spmd.irecv.*():

signature(x = "ANY")

signature(x = "integer")

signature(x = "numeric")

signature(x = "raw")

Author

Wei-Chen Chen , George Ostrouchov, Drew Schmidt, Pragneshkumar Patel, and Hao Yu.

Details

A corresponding send()/isend() should be evoked at the corresponding rank rank.source.

Warning: irecv() is not safe for R since R is not a thread safe package that a dynamic returning object requires certain blocking or barrier at some where. Current, the default method is equivalent to the default method of recv().

References

Programming with Big Data in R Website: https://pbdr.org/

See Also

recv(), send(), isend().

Examples

if (FALSE) {
### Save code in a file "demo.r" and run with 2 processors by
### SHELL> mpiexec -np 2 Rscript demo.r

spmd.code <- "
### Initialize
suppressMessages(library(pbdMPI, quietly = TRUE))
.comm.size <- comm.size()
.comm.rank <- comm.rank()

### Examples.
N <- 5
x <- (1:N) + N * .comm.rank
if(.comm.rank == 0){
  y <- send(matrix(x, nrow = 1))
} else if(.comm.rank == 1){
  y <- irecv()
}
comm.print(y, rank.print = 1)

### Finish.
finalize()
"
# execmpi(spmd.code, nranks = 2L)
}