nc_open_par {pbdNCDF4} | R Documentation |
Opens an existing NetCDF file for reading (or, optionally, writing) in parallel.
nc_open_par(filename, write = FALSE, readunlim = TRUE, verbose = FALSE, comm = 0L, info = 0L)
filename |
Name of the existing NetCDF file to be opened. |
write |
If FALSE (default), then the file is opened read-only. If TRUE, then writing to the file is allowed. |
readunlim |
When invoked, this function reads in the values of all
dimensions from the associated variables. This can be
slow for a large file with a long unlimited dimension.
If set to FALSE, the values for the unlimited dimension
are not automatically read in (they can be read in later,
manually, using |
verbose |
If TRUE, then messages are printed out during execution of this function. |
comm |
a communicator number from pbdMPI. |
info |
a info number from pbdMPI. |
See nc_open
details. The parallel version
is able to coordinate with other nc_open_par
instances for more efficient operation in parallel.
An object of class ncdf4
that has the fields described above.
George Ostrouchov, Pragneshkumar Patel pragnesh@utk.edu, Wei-Chen Chen, and Drew Schmidt.
Programming with Big Data in R Website: http://r-pbd.org/
nc_create_par
, nc_var_par_access
,
ncdim_def
, ncvar_def
.
## Not run: ### Under command mode, run the demo with 2 processors by ### (Use Rscript.exe for windows system) mpiexec -np 2 Rscript -e "demo(ncwrite,'pbdNCDF4',ask=F,echo=F)" mpiexec -np 2 Rscript -e "demo(ncread,'pbdNCDF4',ask=F,echo=F)" ## End(Not run)