Extract.hdf5 {rhdf5}R Documentation

Extract Parts of an HDF5 object.

Description

These are subset operators for HDF5 objects. The name provides specialization (often via method dispatch) for the different specific types of HDF5 objects.

Usage

  x[i]
  x[i, j, ...]
  x[i, j, ..., drop=TRUE]
  x$name

Arguments

x An object of class hdf5.
i An index into the object.
j An index into the object.
... Optional arguments.
drop A logical value, if TRUE the result is coerced to the lowest possible dimension
name The element of a file or group to extract.

Details

These operations only make sense for specific types of HDF5 objects. The names of the functions indicate their specialization. There is currently no [[ operator.

For HDF5 groups and files the $ operator extracts the appropriate element.

Value

For the $ operator an HDF5 object of the appropriate class is returned. For the [ operator an R vector containing the subset is returned. It is envisaged that at some point we may make the [ operator smarter and allow the return of an HDF5 object in situations where the returned value will be very large.

Author(s)

B. Ellis and R. Gentleman

See Also

hdf5.dataset

Examples

 ## Not run: 
 mad <- hdf5.open("microarray.h5")
  hdf5.group(mad,"chip1")
  hdf5.group(mad$chip1,"group")
  hdf5.group.rm(mad$chip1,"group")
  x1 <- hdf5.dataset(mad$chip1, "AA", dim=c(5, 5))
  x1[,1, drop=FALSE]
## End(Not run)
[Package rhdf5 version 1.4.0 Index]