/*
	Read data from an HDF4 file.
	Assume the array has been setup correctly.
	If mode is 0 then just read the rank and dim data.
	If mode is 1 then read the data as well.
*/
int ReadHDF(char *filename,float *array,int *rank,int *dims,int mode)
{ 
   int sd_id, sds_id, sds_idx; 
   int n_datasets, n_file_attrs; 
   int start[2], edges[2]; 
   int num_type, attributes; 
   intn istat; 
   char name[64]="\0"; 
   int i;

   // Read data back and write to a new array 
   if ((sd_id = SDstart(filename, DFACC_READ)) == FAIL) {
		fprintf(stderr,"SDstart() failed\n");
		return(FALSE);
	}

	// Determine the contents of the file.
  	istat = SDfileinfo(sd_id,&n_datasets,&n_file_attrs); 
  	sds_idx = SDnametoindex (sd_id,"image_data"); 

  	if (sds_idx == FAIL)    // norm/sino/recon data sets 
     	sds_idx = SDnametoindex(sd_id,"data"); 

  	sds_id = SDselect (sd_id, sds_idx); 
      
	// Read from file: rank, dims, num_type and attribute 
  	istat = SDgetinfo(sds_id,name,rank,dims,&num_type,&attributes); 
	//fprintf(stderr,"Rank: %d\n",*rank);

	if (mode == 1) {
  		// Define the location, and size of the data set 
   	for (i=0;i<*rank;i++) { 
   	   start[i] = 0; 
   	   edges[i] = dims[i]; 
			//fprintf(stderr,"   Rank: %d, dimension: %d\n",i,dims[i]);
   	} 
   	istat = SDreaddata(sds_id,start,NULL,edges,array); 
	}

   // Terminate access to the array. 
   istat = SDendaccess(sds_id); 

   // Terminate access to the SD interface and close the file. 
   istat = SDend(sd_id); 

   return(TRUE);
}