Sets the size of parameters used to control the symbol table nodes
Procedure:
H5P_SET_SYM_K ( fcpl_id, ik, lk )
Signature:
herr_t H5Pset_sym_k(
hid_t fcpl_id,
unsigned ik,
unsigned lk
)
Fortran90 Interface: h5pset_sym_k_f
SUBROUTINE h5pset_sym_k_f (prp_id, ik, lk, hdferr)
IMPLICIT NONE
INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
INTEGER, INTENT(IN) :: ik ! Symbol table tree rank
INTEGER, INTENT(IN) :: lk ! Symbol table node size
INTEGER, INTENT(OUT) :: hdferr ! Error code
! 0 on success and -1 on failure
END SUBROUTINE h5pset_sym_k_f
Parameters:
hid_t fcpl_id | IN: File creation property list identifier |
unsigned ik | IN: Symbol table tree rank |
unsigned lk | IN: Symbol table node size |
Description:
H5P_SET_SYM_K sets the size of parameters used to control the symbol table nodes.
This function is valid only for file creation property lists. Passing in a value of zero (0
) for one of the parameters retains the current value.
ik
is one half the rank of a B-tree that stores a symbol table for a group. Internal nodes of the symbol table are on average 75% full. That is, the average rank of the tree is 1.5 times the value of ik
. The HDF5 library uses (ik*2)
as the maximum # of entries before splitting a B-tree node. Since only 2 bytes are used in storing # of entries for a B-tree node in an HDF5 file, (ik*2)
cannot exceed 65536
. The default value for ik
is 16
.
lk
is one half of the number of symbols that can be stored in a symbol table node. A symbol table node is the leaf of a symbol table tree which is used to store a group. When symbols are inserted randomly into a group, the group's symbol table nodes are 75% full on average. That is, they contain 1.5 times the number of symbols specified by lk
. The default value for lk
is 4
.
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Example:
History:
Release | Change |
---|
1.6.4 | ik parameter type changed to unsigned. |
1.6.0 | The ik parameter has changed from type int to unsigned. |
--- Last Modified: May 01, 2019 | 03:19 PM