Writing compound datasets of two dimensional datatypes

[flappah]

Hi Lior,

Again, another question. Is there any way to write a compound dataset of a two dimensional custom data type? For example this:

            var surfaceCurrent2DItems = new SurfaceCurrentInstance[3, 3];
            surfaceCurrent2DItems[0, 0] = new SurfaceCurrentInstance(speed: 1.61, direction: 50.9);
            surfaceCurrent2DItems[0, 1] = new SurfaceCurrentInstance(speed: 1.58, direction: 53.4);
            surfaceCurrent2DItems[0, 2] = new SurfaceCurrentInstance(speed: 1.54, direction: 56.1);
            surfaceCurrent2DItems[1, 0] = new SurfaceCurrentInstance(speed: 1.61, direction: 50.9);
            surfaceCurrent2DItems[1, 1] = new SurfaceCurrentInstance(speed: 1.5, direction: 59.0);
            surfaceCurrent2DItems[1, 2] = new SurfaceCurrentInstance(speed: 1.46, direction: 61.9);
            surfaceCurrent2DItems[2, 0] = new SurfaceCurrentInstance(speed: 1.42, direction: 65.1);
            surfaceCurrent2DItems[2, 1] = new SurfaceCurrentInstance(speed: 1.39, direction: 68.4);
            surfaceCurrent2DItems[2, 2] = new SurfaceCurrentInstance(speed: 1.35, direction: 71.9);

            Hdf5.WriteCompounds(group001Id, "values", surfaceCurrent2DItems, new Dictionary<string, List<string>>());

I know this won't work since it's not an IEnumerable. But is there any other way to get this going through the Hdf5 Csharp library? I also know using PureHDF won't work since that one only enables me to read compound datasets, not writing. Any ideas?

[edit]
Oh yeah, and this is the definition of SurfaceCurrentInstance:

    public struct SurfaceCurrentInstance
    {
        [Hdf5EntryName("surfaceCurrentSpeed")]
        public double speed;

        [Hdf5EntryName("surfaceCurrentDirection")]
        public double direction;

        /// <summary>
        ///     
        /// </summary>
        /// <param name="height"></param>
        /// <param name="trend"></param>
        public SurfaceCurrentInstance(double speed, double direction)
        {
            this.speed = speed;
            this.direction = direction;
        }
    }

[LiorBanai]

Hi,
I'll have to take a look to answer correctly.
Hopefully I'll be able to do it next week

[flappah]

Also for this one I got around the issue by adding my own implementation. It’s an ugly one but I just made an extension method that I could call if I had to write 2D arrays. I’ll add my code to this issue tomorrow since I’ve only got it on usb stick. I literally looked at your code and MacGyver’ed my way through it. :)
I’ll add it tomorrow!

[LiorBanai]

MacGyvering stuff is the best approach to bypass limitations hh

[flappah]

Hahaha .. true! True!

This is the helper class I'm using:

using HDF.PInvoke;
using System.Runtime.InteropServices;

namespace Hdf5Fase2Test.Hdf5
{
    public class Hdf5Extensions
    {
        /// <summary>
        /// 
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="groupId"></param>
        /// <param name="name"></param>
        /// <param name="data"></param>
        /// <param name="attributes"></param>
        /// <returns></returns>
        public static (int success, long createdGroupId) Write2DCompounds<T>(long groupId, string name, T[,] data, Dictionary<string, List<string>> attributes)
        {
            long spaceId = H5S.create_simple(2, new ulong[] { (ulong)data.GetLength(0), (ulong)data.GetLength(1) }, null);
            long dataTypeId = HDF5CSharp.Hdf5.CreateType(typeof(T));
            GCHandle? handleStorage = null;
            int statusId = -1;
            try
            {
                handleStorage = GCHandle.Alloc(data, GCHandleType.Pinned);
                long datasetId = H5D.create(groupId, name, dataTypeId, spaceId);
                statusId = H5D.write(datasetId, dataTypeId, spaceId, H5S.ALL, H5P.DEFAULT, ((GCHandle) handleStorage).AddrOfPinnedObject());

                H5D.close(datasetId);
                H5T.close(dataTypeId);
                H5S.close(spaceId);
            }
            finally
            {
                if (handleStorage != null)
                {
                    ((GCHandle)handleStorage).Free();
                }
            }


            return (statusId, dataTypeId);
        }
    }
}