The following H5S functions are included in the HDF5 specification, but have not yet been implemented. They are described in the The Dataspace Interface (H5S) section of the HDF5 User's Guide..
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H5Screate(H5S_class_t type)
H5Screate creates a new dataspace of a particular
type.
The types currently supported are H5S_SCALAR,
H5S_SIMPLE, and H5S_NONE;
others are planned to be added later. The H5S_NONE
dataspace can only hold a selection, not an extent.
type
H5Screate_simple(int rank,
const hsize_t * dims,
const hsize_t * maxdims
)
H5Screate_simple creates a new simple data space
and opens it for access. The rank is the number of
dimensions used in the dataspace.
The dims argument is the size
of the simple dataset and the maxdims argument is
the upper limit on the size of the dataset. maxdims
may be the null pointer in which case the upper limit is the
same as dims. If an element of maxdims
is zero then the corresponding dimension is unlimited, otherwise
no element of maxdims should be smaller than the
corresponding element of dims. The dataspace
identifier returned from this function should be released with
H5Sclose or resource leaks will occur.
rank
dims
maxdims
H5Scopy(hid_t space_id
)
H5Scopy creates a new dataspace which is an exact
copy of the dataspace identified by space_id.
The dataspace identifier returned from this function should be
released with H5Sclose or resource leaks will occur.
space_id
H5Sselect_elements(hid_t space_id,
dh5s_selopt_t op,
const size_t num_elements,
const hssize_t *coord[ ]
)
H5Sselect_elements selects array elements to be
included in the selection for the space_id
dataspace. The number of elements selected must be set with
the num_elements. The coord array
is a two-dimensional array of size dataspace rank
by num_elements (ie. a list of coordinates in
the array). The order of the element coordinates in the
coord array also specifies the order in which
the array elements are iterated through when I/O is performed.
Duplicate coordinate locations are not checked for.
The selection operator op determines how the
new selection is to be combined with the previously existing
selection for the dataspace. Currently, only the
H5S_SELECT_SET operator is supported, which
replaces the existing selection with the parameters from
this call. When operators other than H5S_SELECT_SET
are used to combine a new selection with an existing selection,
the selection ordering is reset to 'C' array ordering.
space_id
op
num_elements
coord[ ]
H5Sselect_all(hid_t space_id)
H5Sselect_all selects the entire extent
of the dataspace space_id.
More specifically, H5Sselect_all selects
the special 5S_SELECT_ALL region for the dataspace
space_id. H5S_SELECT_ALL selects the
entire dataspace for any dataspace it is applied to.
space_id
H5Sselect_none(hid_t space_id)
H5Sselect_none resets the selection region
for the dataspace space_id to include no elements.
space_id
H5Sselect_valid(hid_t space_id)
H5Sselect_valid verifies that the selection
for the dataspace space_id is within the extent
of the dataspace if the current offset for the dataspace is used.
space_id
H5Sget_simple_extent_npoints(hid_t space_id)
H5Sget_simple_extent_npoints determines the number of elements
in a dataspace. For example, a simple 3-dimensional dataspace
with dimensions 2, 3, and 4 would have 24 elements.
space_id
H5Sget_select_npoints(hid_t space_id)
H5Sget_select_npoints determines the number of elements
in the current selection of a dataspace.
space_id
H5Sget_simple_extent_ndims(hid_t space_id)
H5Sget_simple_extent_ndims determines the dimensionality (or rank)
of a dataspace.
space_id
H5Sget_simple_extent_dims(hid_t space_id,
hsize_t *dims,
hsize_t *maxdims
)
H5Sget_simple_extent_dims returns the size and maximum sizes
of each dimension of a dataspace through the dims
and maxdims parameters.
space_id
dims
maxdims
H5Sget_simple_extent_type(hid_t space_id)
H5Sget_simple_extent_type queries a dataspace to determine the
current class of a dataspace.
The function returns a class name, one of the following:
H5S_SCALAR,
H5S_SIMPLE, or
H5S_NONE.
space_id
H5Sset_extent_simple(hid_t space_id,
int rank,
const hsize_t *current_size,
const hsize_t *maximum_size
)
H5Sset_extent_simple sets or resets the size of
an existing dataspace.
rank is the dimensionality, or number of
dimensions, of the dataspace.
current_size is an array of size rank
which contains the new size of each dimension in the dataspace.
maximum_size is an array of size rank
which contains the maximum size of each dimension in the
dataspace.
Any previous extent is removed from the dataspace, the dataspace
type is set to H5S_SIMPLE, and the extent is set as
specified.
space_id
rank
current_size
maximum_size
H5Sis_simple(hid_t space_id)
H5Sis_simple determines whether a dataspace is
a simple dataspace. [Currently, all dataspace objects are simple
dataspaces, complex dataspace support will be added in the future]
space_id
H5Soffset_simple(hid_t space_id,
const hssize_t *offset
)
H5Soffset_simple sets the offset of a
simple dataspace space_id. The offset
array must be the same number of elements as the number of
dimensions for the dataspace. If the offset
array is set to NULL, the offset for the dataspace
is reset to 0.
This function allows the same shaped selection to be moved to different locations within a dataspace without requiring it to be redefined.
space_id
offset
H5Sextent_class(hid_t space_id)
H5Sextent_class queries a dataspace to determine the
current class of a dataspace.
The function returns a class name, one of the following:
H5S_SCALAR,
H5S_SIMPLE.
space_id
H5Sextent_copy(hid_t dest_space_id,
hid_t source_space_id
)
H5Sextent_copy copies the extent from
source_space_id to dest_space_id.
This action may change the type of the dataspace.
dest_space_id
source_space_id
H5Sset_extent_none(hid_t space_id)
H5Sset_extent_none removes the extent from
a dataspace and sets the type to H5S_NONE.
space_id
H5Sselect_hyperslab(hid_t space_id,
h5s_selopt_top,
const hssize_t *start,
const hsize_t *stride
const hsize_t *count,
const hsize_t *block
)
H5Sselect_hyperslab selects a hyperslab region
to add to the current selected region for the dataspace
specified by space_id.
The start, stride, count,
and block arrays must be the same size as the rank
of the dataspace.
The selection operator op determines how the new
selection is to be combined with the already existing selection
for the dataspace.
Currently, only the H5S_SELECT_SET operator is
supported; it replaces the existing selection with the
parameters from this call. Overlapping blocks are not
supported with the H5S_SELECT_SET operator.
The start array determines the starting coordinates
of the hyperslab
to select.
The stride array chooses array locations
from the dataspace
with each value in the stride array determining how
many elements to move
in each dimension. Setting a value in the stride
array to 1 moves to
each element in that dimension of the dataspace; setting a value of 2 in a
location in the stride array moves to every other
element in that
dimension of the dataspace. In other words, the stride
determines the
number of elements to move from the start location
in each dimension.
Stride values of 0 are not allowed. If the stride
parameter is NULL,
a contiguous hyperslab is selected (as if each value in the
stride array
was set to all 1's).
The count array determines how many blocks to
select from the dataspace, in each dimension.
The block array determines
the size of the element block selected from the dataspace.
If the block
parameter is set to NULL, the block size defaults
to a single element
in each dimension (as if the block array was set to all 1's).
For example, in a 2-dimensional dataspace, setting
start to [1,1],
stride to [4,4], count to [3,7], and
block to [2,2] selects
21 2x2 blocks of array elements starting with location (1,1) and selecting
blocks at locations (1,1), (5,1), (9,1), (1,5), (5,5), etc.
Regions selected with this function call default to C order iteration when I/O is performed.
space_id
op
start
count
stride
block
H5Sclose(hid_t space_id
)
H5Sclose releases a dataspace.
Further access through the dataspace identifier is illegal.
Failure to release a dataspace with this call will
result in resource leaks.
space_id