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HDF5CreateGroup

HDF5CreateGroup [ /Z ] locationID, nameStr, groupID​

The HDF5CreateGroup operation creates an HDF5 group in the HDF5 file. It returns a group ID via groupID.

If the specified group already exists, HDF5CreateGroup just returns a group ID via groupID.

You can close the group by calling HDF5CloseGroup when you are finished with it. If you do no close a group, it is closed when you close the file using HDF5CloseFile.

Parameters​

locationID is an HDF5 file ID number obtained from HDF5CreateFile or HDF5OpenFile or an HDF5 group ID obtained from HDF5CreateGroup or HDF5OpenGroup. If locationID is invalid an error is returned.

nameStr is a string containing the HDF5 path to the group to be created. This can be a full HDF5 path or a simple name or partial HDF5 path relative to locationID.

For example, to create a group named GroupA at the root level of the file, you would pass the HDF5 file ID as the locationID parameter and "GroupA" or "/GroupA" as the nameStr parameter.

To create a group named GroupB inside GroupA, you could pass any of the following:

locationID = any file or group ID and nameStr = "/GroupA/GroupB"
locationID = file ID and nameStr = "GroupA/GroupB"
locationID = GroupA ID and nameStr = "GroupB"

HDF5CreateGroup creates just one group. For example, if you pass "/GroupA/GroupB" as locationID then GroupA must already exist in the root. Otherwise HDF5CreateGroup returns an error.

groupID is the name of an Igor local variable or NVAR referencing a global variable. HDF5CreateGroup returns an HDF5 group ID number in the named variable. You pass this group ID to subsequent HDF5 operation and function calls and to HDF5CloseGroup when you are finished with the group. If for some reason the HDF5CreateGroup operation fails, groupID is set to zero.

Flags​

/SIZE=groupSizegroupSize is the suggested number of bytes to reserve to store the names which will be eventually added to the new group. This flag is for advanced HDF5 users only. groupSize is passed as the size_hint parameter to the HDF5 library's H5Gcreate function.
/ZSuppress error generation. Use this if you want to handle errors yourself.

Output Variables​

HDF5CreateGroup sets the following output variable:

V_FlagSet to zero if the operation succeeds, non-zero if it fails.