The HDF_SD_IDTOREF function converts a SD data set ID into a SD data set reference number. The reference number can be used to add the SD data set to a Vgroup through the HDF_VG interface. The tag number for an SD is 720.

Examples


; Create an SD data set and get the Reference number:
file_id = HDF_OPEN('demo.hdf', /ALL)
SDinterface_id = HDF_SD_START('demo.hdf', /RDWR)
dim=[100]
SDdataset_id = HDF_SD_CREATE(SDinterface_id, 'demo_data', dim, /FLOAT)
ref = HDF_SD_IDTOREF(SDdataset_id)
HDF_SD_ADDDATA, SDdataset_id, FINDGEN(100)/10.45 + 2.98
HDF_SD_ENDACCESS, SDdataset_id
HDF_SD_END, SDinterface_id
 
; Use the Reference number to add the SD to a Vgroup:
SD_TAG = 720
vgID = HDF_VG_GETID(file_id,-1)
vg_handle = HDF_VG_ATTACH(file_id, vgID, /WRITE)
HDF_VG_SETINFO, vg_handle, name='data1', class='demo'
HDF_VG_ADDTR, vg_handle, SD_TAG, ref
 
; Use HDF_VG_INQTR to verify the SD was added correctly:
IF HDF_VG_INQTR(vg_handle, SD_TAG, ref) THEN $
   PRINT, 'SUCCESS' ELSE PRINT, 'Failure'
HDF_VG_DETACH, vg_handle
HDF_CLOSE, file_id

IDL Output

SUCCESS

Syntax


Result = HDF_SD_IDTOREF(SDdataset_id)

Return Value


Returns the SD data set reference number.

Arguments


SDdataset_id

A SDdataset_id as returned from HDF_SD_CREATE or HDF_SD_SELECT.

Keywords


None

Version History


4.0

Introduced

See Also


HDF_SD_CREATE, HDF_SD_NAMETOINDEX, HDF_SD_REFTOINDEX, HDF_SD_SELECT, HDF_VG_ADDTR, HDF_VG_ATTACH, HDF_VG_DETACH, HDF_VG_GETID, HDF_VG_INQTR