[Hdf-forum] H5Dcreate2() bug?

[Quincey Koziol]

Hi Xunlei,

On Jan 10, 2010, at 4:43 PM, Xunlei Wu wrote:

> Hi All,
> 
> Reporting a weird behavior involving H5Dcreate2(). The only difference
> between 2 below code sections is using "pos" or "position" as the second
> parameter of H5Dcreate2(). I am wondering whether "position" is a
> reserved word/macro in HDF5. When using "position", all the elements
> written in the .h5 file become -4.3160208E8. Please help.

	There are no reserved names for objects in HDF5 files.  This sort of behavior typically indicates a memory overwrite somewhere in the application.  I suggest running it with valgrind to see if you can locate the problem.

	Quincey


> Best,
> xunlei
> 
> //---- below code writes INVALID data ----
> /*allocate space, initialization, and etc.*/
> ...
> dim[0] = 100;
> dim[1] = 3;
> for(int j=0; j<dim[0]; j++){
> val_f[ j] = ps[i][j].x;
> val_f[ dim[0] + j] = ps[i][j].y;
> val_f[2 * dim[0] + j] = ps[i][j].z;
> }
> 
> space_id = H5Screate_simple(2, dim, NULL);
> dataset_id = H5Dcreate(group_frame_id, "position", H5T_IEEE_F32BE,
> space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
> /* Write data to the dataset; */
> status = H5Dwrite(dataset_id, H5T_NATIVE_FLOAT, space_id, H5S_ALL,
> H5P_DEFAULT, val_f);
> 
> H5Sclose(space_id);
> H5Dclose(dataset_id);
> 
> //---- below code writes CORRECT data ----
> /*allocate space, initialization, and etc.*/
> ...
> dim[0] = 100;
> dim[1] = 3;
> for(int j=0; j<dim[0]; j++){
> val_f[ j] = ps[i][j].x;
> val_f[ dim[0] + j] = ps[i][j].y;
> val_f[2 * dim[0] + j] = ps[i][j].z;
> }
> 
> space_id = H5Screate_simple(2, dim, NULL);
> dataset_id = H5Dcreate(group_frame_id, "pos", H5T_IEEE_F32BE, space_id,
> H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
> /* Write data to the dataset; */
> status = H5Dwrite(dataset_id, H5T_NATIVE_FLOAT, space_id, H5S_ALL,
> H5P_DEFAULT, val_f);
> 
> H5Sclose(space_id);
> H5Dclose(dataset_id);
> 
> 
> _______________________________________________
> Hdf-forum is for HDF software users discussion.
> Hdf-forum at hdfgroup.org
> http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org