The HDF_SD_GETDATA procedure retrieves a hyperslab of values from an SD dataset. By default, the retrieved data is transposed from HDF's column order format into IDL's row order which is more efficient in IDL. To retrieve the dataset without this transposition, set the NOREVERSE keyword.
Set this keyword to a vector containing the counts, or number of items, to be read. The default is to read all available data.
Set the keyword to retrieve the data without transposing the data from column to row order.
For an example using this routine, see the documentation for HDF_SD_ADDDATA