/* This example shows how to read a data field in HDF-EOS2 grid data. */

#include <mfhdf.h>
#include <hdf.h>
#include <HdfEosDef.h>
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
	int32 gridfile1;
	int32 grid1;
	int32 datafield1rank;
	int32 datafield1dimsize[32];
	int32 datafield1type;
	char datafield1dimname[512];
	int16 *datafield1data;
	int32 i, j;

	/* Open 'MCD43C4.A2000049.005.2006271205532.hdf' using grid API */
	if ((gridfile1 = GDopen("MCD43C4.A2000049.005.2006271205532.hdf", DFACC_RDONLY)) == -1) {
		fprintf(stderr, "error: cannot open grid 'MCD43C4.A2000049.005.2006271205532.hdf'\n");
		return -1;
	}

	/* Open a grid named 'MCD_CMG_BRDF_0.05Deg' */
	if ((grid1 = GDattach(gridfile1, "MCD_CMG_BRDF_0.05Deg")) == -1) {
		fprintf(stderr, "error: cannot attach to 'MCD_CMG_BRDF_0.05Deg'\n");
		return -1;
	}

	/* Retrieve information about 'Nadir_Reflectance_Band1' datafield */
	if ((GDfieldinfo(grid1, "Nadir_Reflectance_Band1", &datafield1rank, datafield1dimsize, &datafield1type, datafield1dimname)) == -1) {
		fprintf(stderr, "error: cannot get the field info for 'Nadir_Reflectance_Band1'\n");
		return -1;
	}
	/* Allocate buffer for 'Nadir_Reflectance_Band1' */
	if ((datafield1data = malloc(sizeof(int16) * 3600 * 7200)) == NULL) {
		fprintf(stderr, "error: cannot allocate memory for 'Nadir_Reflectance_Band1'\n");
		return -1;
	}
	/* Read data from 'Nadir_Reflectance_Band1' */
	if ((GDreadfield(grid1, "Nadir_Reflectance_Band1", NULL, NULL, NULL, datafield1data)) == -1) {
		fprintf(stderr, "error: cannot read field 'Nadir_Reflectance_Band1'\n");
		return -1;
	}
	/* Dump data from 'Nadir_Reflectance_Band1' */
	for (i = 0; i < 36; ++i) {
		for (j = 0; j < 72; ++j) {
			printf("%d ", datafield1data[j + 7200 * i]);
		}
		printf("\n");
	}
	/* Release the buffer for 'Nadir_Reflectance_Band1' */
	free(datafield1data);

	/* Close the grid named 'MCD_CMG_BRDF_0.05Deg' */
	if ((GDdetach(grid1)) == -1) {
		fprintf(stderr, "error: cannot detach from 'MCD_CMG_BRDF_0.05Deg'\n");
		return -1;
	}

	/* Close 'MCD43C4.A2000049.005.2006271205532.hdf' */
	if ((GDclose(gridfile1)) == -1) {
		fprintf(stderr, "error: cannot close grid 'MCD43C4.A2000049.005.2006271205532.hdf'\n");
		return -1;
	}

	return 0;
}