The HDF_VD_INSERT procedure adds a VData or VGroup to the contents of a VGroup in an HDF file.
HDF_VD_INSERT, VGroup, VData(or Vgroup)[, POSITION=variable]
The VGroup handle returned by a previous call to HDF_VG_ATTACH.
The VData (or VGroup) handle returned by HDF_VD_ATTACH (HDF_VG_ATTACH).
Set this keyword to return the entry position of the element (VData or VGroup, respectively) within the existing VGroup to which you are adding.