Tuan, On Aug 12, 2010, at 8:12 PM, Hoang Trong Minh Tuan wrote:
> Hi all, > I read from the SZIP information page that the chunk's fastest-changing > dimension should be equal to N times pixel_per_block where N is the maximum > number of blocks per scan line (N=128). > For a 2D array in C, the fastest changing dimension is the column; while > it is the row in Fortran. I'm using Fortran wrapper for HDF5 which should > call C implementation of HDF5. So, I'm not sure if I'm coding in Fortran, > should I use the row in Fortran matrix as the fastest-changing dimension or > the column in order to achieve the better performance? > In C fastest changing dimension is row, and in Fortran it is column Consider matrix 1 2 3 4 5 6 This matrix is stored as 1 2 3 4 5 6 from C, while from Fortran it will be stored as 1 4 2 5 3 6 So, use Fortran's column size. Elena > > Thank you, > > Tuan > > _______________________________________________ > 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
