H5L.visit_by_name

Recursively iterate through links in group specified by location and group name

Syntax

[status,opdata_out] = H5L.visit_by_name(loc_id,group_name,index_type,order,iter_func,opdata_in,lapl_id)

Description

[status,opdata_out] = H5L.visit_by_name(loc_id,group_name,index_type,order,iter_func,opdata_in,lapl_id) recursively iterates though all links in and below a group to perform a common function whose function handle is iter_func. The starting point of the iteration is specified by the pairing of a location id and a relative group name. A link access property list, lapl_id, may affect the outcome depending upon the type of link being traversed.

index_type and order establish the iteration. index_type specifies the index to be used. If the links have not been indexed by the index type, they are first sorted by that index, and then the iteration will begin. If the links have been so indexed, the sorting step is unnecessary, so the iteration can begin more quickly. Valid values include the following.

'H5_INDEX_NAME'Alpha-numeric index on name
'H5_INDEX_CRT_ORDER'Index on creation order

Note that the index type passed in index_type is a best effort setting. If the application passes in a value indicating iteration in creation order and a group is encountered that was not tracked in creation order, that group will be iterated over in alpha-numeric order by name, or name order. (Name order is the native order used by the HDF5 Library and is always available.)

order specifies the order in which objects are to be inspected along the index specified in index_type. Valid values include the following.

'H5_ITER_INC'Increasing order
'H5_ITER_DEC'Decreasing order
'H5_ITER_NATIVE'Fastest available order

The callback function iter_func must have the following signature:

function [status,opdata_out] = iter_func(group_id,name,opdata_in)

opdata_in is a user-defined value or structure and is passed to the first step of the iteration in the iter_func opdata_in parameter. The opdata_out of an iteration step forms the opdata_in for the next iteration step. The final opdata_out at the end of the iteration is then returned to the caller as opdata_out.

status value returned by iter_func is interpreted as follows.

zeroContinues with the iteration or returns zero status value to the caller if all members have been processed
positiveStops the iteration and returns the positive status value to the caller
negativeStops the iteration and throws an error indicating failure

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