/* This example shows how to read a data field in HDF-EOS5 grid data. */

#include <HE5_HdfEosDef.h>
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
	hid_t gridfile1;
	hid_t grid1;
	int datafield1rank;
	hsize_t datafield1dimsize[32];
	hid_t datafield1type;
	char datafield1dimname[512];
	char datafield1maxdimname[512];
	float *datafield1data;
	hsize_t i, j;

	/* Open 'TES-Aura_L3-CH4_r0000002135_F01_05.he5' using grid API */
	if ((gridfile1 = HE5_GDopen("TES-Aura_L3-CH4_r0000002135_F01_05.he5", H5F_ACC_RDONLY)) == -1) {
		fprintf(stderr, "error: cannot open grid 'TES-Aura_L3-CH4_r0000002135_F01_05.he5'\n");
		return -1;
	}

	/* Open a grid named 'NadirGrid' */
	if ((grid1 = HE5_GDattach(gridfile1, "NadirGrid")) == -1) {
		fprintf(stderr, "error: cannot attach to 'NadirGrid'\n");
		return -1;
	}

	/* Retrieve information about 'CH4AtSurface' datafield */
	if ((HE5_GDfieldinfo(grid1, "CH4AtSurface", &datafield1rank, datafield1dimsize, &datafield1type, datafield1dimname, datafield1maxdimname)) == -1) {
		fprintf(stderr, "error: cannot get the field info for 'CH4AtSurface'\n");
		return -1;
	}
	/* Allocate buffer for 'CH4AtSurface' */
	if ((datafield1data = malloc(sizeof(float) * 90 * 83)) == NULL) {
		fprintf(stderr, "error: cannot allocate memory for 'CH4AtSurface'\n");
		return -1;
	}
	/* Read data from 'CH4AtSurface' */
	if ((HE5_GDreadfield(grid1, "CH4AtSurface", NULL, NULL, NULL, datafield1data)) == -1) {
		fprintf(stderr, "error: cannot read field 'CH4AtSurface'\n");
		return -1;
	}
	/* Dump data from 'CH4AtSurface' */
	for (i = 0; i < 9; ++i) {
		for (j = 0; j < 8; ++j) {
			printf("%f ", datafield1data[j + 83 * i]);
		}
		printf("\n");
	}
	/* Release the buffer for 'CH4AtSurface' */
	free(datafield1data);

	/* Close the grid named 'NadirGrid' */
	if ((HE5_GDdetach(grid1)) == -1) {
		fprintf(stderr, "error: cannot detach from 'NadirGrid'\n");
		return -1;
	}

	/* Close 'TES-Aura_L3-CH4_r0000002135_F01_05.he5' */
	if ((HE5_GDclose(gridfile1)) == -1) {
		fprintf(stderr, "error: cannot close grid 'TES-Aura_L3-CH4_r0000002135_F01_05.he5'\n");
		return -1;
	}

	return 0;
}