The best way to write ref attributes is to use a byte buffer.
However, if an attribute is a single value of reference, using
the object path will also work. Here is an example of using
both ways.
=======================================
H5File file = new H5File(fname, H5File.CREATE);
file.open();
// create a ref dataset
Group grp = file.createGroup("grp", null);
Dataset ds = file.createScalarDS("dset", grp, new
H5Datatype(Datatype.CLASS_FLOAT, -1, -1, -1), dims, maxdims, null, 0, data);
ref_buf[0] = H5.H5Rcreate(file.getFID(), grp.getFullName(),
HDF5Constants.H5R_OBJECT, -1);
ref_buf[1] = H5.H5Rcreate(file.getFID(), ds.getFullName(),
HDF5Constants.H5R_OBJECT, -1);
ds = file.createScalarDS(dname, null, new
H5Datatype(Datatype.CLASS_REFERENCE, -1, -1, -1), new long[] {2}, null,
null, 0, ref_buf);
// create ref attributes
Datatype attr_dtype = file.createDatatype(
Datatype.CLASS_REFERENCE, Datatype.NATIVE, Datatype.NATIVE,
Datatype.NATIVE);
Attribute attr = new Attribute("ref", attr_dtype, new long[] {1});
attr.setValue(ds.getFullName());
file.writeAttribute(ds, attr, false);
attr = new Attribute("refs", attr_dtype, new long[] {2});
attr.setValue(ref_buf);
ds.writeMetadata(attr);
file.close();
===================================================
On 3/30/2011 9:11 AM, Konrad Hinsen wrote:
On 28 Mar, 2011, at 19:11 , Peter Cao wrote:
Try this:
===============
// open the file and the dataset with refs
file.open();
ds = (H5ScalarDS)file.get(dname);
long[] refs = (long[])ds.getData();
// use low level API function, H5.H5Rget_name
String[] name = {""};;
for (int i=0; i<refs.length; i++) {
H5.H5Rget_name(file.getFID(), HDF5Constants.H5R_OBJECT,
HDFNativeData.longToByte(refs[i]), name, 32);
System.out.println(name[0]);
}
// if file.open() was called, search objects in memory by high level
function, findObject()
long[] oid = new long[1];
for (int i=0; i<refs.length; i++) {
oid[0] = refs[i];
HObject obj = FileFormat.findObject(file, oid);
System.out.println(obj.getFullName());
}
==============
I am now at the point where I would like to write reference attributes as well.
But what do I supply as the attribute value? I first tried to provide the
objects themselves, but that results in invalid references. A look at the
source code (H5File.java) shows that there is a special case for a single
reference which can be supplied as a string (path to the object). So I tried an
array of strings, but that also leads to invalid references. Do I have to use
the low-level routines again for some conversion?
Konrad.
--
---------------------------------------------------------------------
Konrad Hinsen
Centre de Biophysique Moléculaire, CNRS Orléans
Synchrotron Soleil - Division Expériences
Saint Aubin - BP 48
91192 Gif sur Yvette Cedex, France
Tel. +33-1 69 35 97 15
E-Mail: research AT khinsen DOT fastmail DOT net
---------------------------------------------------------------------
_______________________________________________
Hdf-forum is for HDF software users discussion.
[email protected]
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org
_______________________________________________
Hdf-forum is for HDF software users discussion.
[email protected]
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org
