Last modified: 16 September 2015

Signature:

herr_t H5Pset_chunk(hid_t plist, int ndims, const hsize_t * dim )

Purpose:

Sets the size of the chunks used to store a chunked layout dataset.

Description:

H5Pset_chunk sets the size of the chunks used to store a chunked layout dataset. This function is only valid for dataset creation property lists.

The ndims parameter currently must be the same size as the rank of the dataset.

The values of the dim array define the size of the chunks to store the dataset's raw data. The unit of measure for dim values is dataset elements.

As a side-effect of this function, the layout of the dataset is changed to H5D_CHUNKED, if it is not already so set. (See H5Pset_layout.)

Notes:

Chunk size cannot exceed the size of a fixed-size dataset. For example, a dataset consisting of a 5x4 fixed-size array cannot be defined with 10x10 chunks.
Chunk maximums

The maximum number of elements in a chunk is 2³²-1 which is equal to 4,294,967,295. If the number of elements in a chunk is set via H5Pset_chunk to a value greater than 2³²-1, then H5Pset_chunk will fail.
The maximum size for any chunk is 4GB. If a chunk that is larger than 4GB attempts to be written with H5Dwrite, then H5Dwrite will fail.

Parameters:

hid_t `plist`	IN: Dataset creation property list identifier.
int `ndims`	IN: The number of dimensions of each chunk.
const hsize_t * `dim`	IN: An array defining the size, in dataset elements, of each chunk.

Returns:

Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_chunk_f

SUBROUTINE h5pset_chunk_f(prp_id, ndims, dims, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier 
  INTEGER, INTENT(IN) :: ndims          ! Number of chunk dimensions
  INTEGER(HSIZE_T), DIMENSION(ndims), INTENT(IN) :: dims    
                                        ! Array containing sizes of
                                        ! chunk dimensions
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pset_chunk_f

History:

Release	Change
1.8.16	Added chunk size limit note to Description.