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RNetCDF (version 2.11-1)

grp.def.nc: Define a NetCDF Group

Description

Define a NetCDF Group.

Usage

grp.def.nc(ncid, grpname)

Value

Object of class NetCDF which points to the NetCDF group, returned invisibly.

Arguments

ncid

Object of class NetCDF which points to the NetCDF dataset (as returned from open.nc) or parent group (as returned by this function).

grpname

Group name. Must begin with an alphabetic character, followed by zero or more alphanumeric characters including the underscore ("_"). Case is significant.

Author

Pavel Michna, Milton Woods

Details

This function may only be used with datasets in netcdf4 format. It creates a new NetCDF group, which may be used as a container for other NetCDF objects, including groups, dimensions, variables and attributes.

Most NetCDF object types, including groups, variables and global attributes, are visible only in the group where they are defined. However, dimensions are visible in their groups and all child groups.

References

https://www.unidata.ucar.edu/software/netcdf/

Examples

Run this code
##  Create a new NetCDF4 dataset
file1 <- tempfile("grp.def_", fileext=".nc")
nc <- create.nc(file1, format="netcdf4")

## Define dimensions, variables and attributes in the root group
dim.def.nc(nc, "station", 5)
var.def.nc(nc, "station", "NC_CHAR", c("station"))
att.put.nc(nc, "NC_GLOBAL", "Description", "NC_CHAR", "Site-based measurements") 

## Define a group
grp <- grp.def.nc(nc, "time_series")

## Define dimensions and variables in the new group
dim.def.nc(grp, "time", unlim=TRUE)
var.def.nc(grp, "time", "NC_INT", "time")
var.def.nc(grp, "temperature", "NC_DOUBLE", c("station","time"))
att.put.nc(nc, "NC_GLOBAL", "Description", "NC_CHAR", "Time-series at sites")

close.nc(nc)
unlink(file1)

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