swapmemory {rhdf5}R Documentation

Functions to handle adding R memory to HDF5 objects.

Description

These functions manipulate memory that is stored using the protected slot in the external reference.

Usage

swapmemory(set1, set2)
addmemory(set1)
freememory(set1)
hasmemory(set1)
getmemory(set1)

Arguments

set1 An HDF5 dataset.
set2 An HDF5 dataset.

Details

Sometimes, in the interest of efficiency we may want to preallocate memory that will subsequently be used to perform calculations on an HDF5 data set. For example, if a number of identical images are going to be processed by a C/Fortran routine then it will be more efficient to allocate one piece of memory and swap it between HDF5 objects.

These functions provide a primitive interface to that functionality.

Value

hasmemory returns TRUE if the HDF5 dataset has memory allocated for it.
freememory sets the memory to NULL and the memory that was stored will be collected by the garbage collector the next time it runs.
swapmemory swaps the memory held by set1 to set2. The memory will be NULL for set1 after this operation.
addmemory adds a vector of R allocated memory that is large enough to hold the entire hdf5 object. At some point in time it might be useful to have the option of allocating for a selected dataspace.
getmemory returns the memory, as a vector. It may not be initialized. This could be an option at some later date.

Author(s)

R. Gentleman

See Also

hdf5

Examples

#we need a testing paradigm


[Package rhdf5 version 1.4.0 Index]