C# code

Hi all,
After my request for help I spotted some dumb things I was doing and got
it all ironed out.

Here is my code in case anyone is either interested in seeing a fairly
minimal C# hyperslab example, or would like to give me any hints on things
I could do in better ways.

best regards,




H5FileId datafile = H5F.open("D:\\kil_Tofdat1.h5", H5F.OpenMode.ACC_RDONLY);
            // Open file on DVD
            H5GroupId groupid = H5G.open(datafile, "FullSpectra");
            // Open Group in file
            H5DataSetId dataid = H5D.open(groupid, "TofData");
            // Open Data Set in group
            H5DataSpaceId filespaceid = H5D.getSpace(dataid);
            // Get Data Space Id for Data Set in file.

            int rank = H5S.getSimpleExtentNDims(filespaceid);
            // Get rank of data from data space (4 in this case)

            ulong[] dims;
            dims = H5S.getSimpleExtentDims(filespaceid);
            // Get the size of the space (returns numbers that match with
HDFView) so seems sensible

            Console.WriteLine("rank {0}, dimensions {1} x {2} x {3} x
{4}\n", rank, dims[0], dims[1], dims[2], dims[3]);

            ulong[] offset = new ulong[rank];
            ulong[] count = new ulong[rank];

            offset[0] = 0;
            offset[1] = 0;
            offset[2] = 0;
            offset[3] = 0;

            count[0] = 1;
            count[1] = 1;
            count[2] = 1;
            count[3] = dims[3];
            // setup counts and offsets to just read 1st "slice" of data

            H5DataSpaceId memspaceid = H5S.create_simple(rank, count, null);
            // create memory Data Space. Is this sane? What about that

            H5S.selectHyperslab(memspaceid, H5S.SelectOperator.SET,
offset, count);
            // select hyperslab in memory data space
            offset[0] = 1;
            offset[1] = 199;

            filespaceid = H5D.getSpace(dataid);
            H5S.selectHyperslab(filespaceid, H5S.SelectOperator.SET,
offset, count);
            // select hyperslab in filespaceid

            double[] readDataBack = new double[dims[3]];//174499
            // Set up memory to read into

            H5D.read(dataid, new H5DataTypeId(H5T.H5Type.NATIVE_DOUBLE),
memspaceid, filespaceid, new H5PropertyListId(new
H5P.Template()), new H5Array<double>(readDataBack));

            Console.WriteLine(" {0} {1} {2} {3} {4} {5} {6}",
readDataBack[51705], readDataBack[51706], readDataBack[51707],
readDataBack[51708], readDataBack[51709], readDataBack[51710],
            Console.WriteLine("Closed file.");

Dr. Mark Neal,
Department of Computer Science,
University of Wales, Aberystwyth,
SY23 3DB,

(+44) 1970 622449

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Here is my attempt at a more general solution. So far one does have to know
the group/dataset name ahead of time.


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