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()
if(.comm.size < 2)
comm.stop(\"At least two processors are requried.\")
### Examples.
if(.comm.rank != 0){
send(as.integer(.comm.rank * 10), rank.dest = 0L,
tag = as.integer(.comm.rank + 10))
}
if(.comm.rank == 0){
for(i in 1:(.comm.size - 1)){
ret <- recv(x.buffer = integer(1),
rank.source = anysource(), tag = anytag())
sourcetag <- get.sourcetag()
print(c(sourcetag, ret))
}
}
### Finish.
finalize()
"
# execmpi(spmd.code, nranks = 2L)
}
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