OS/2 Shareware BBS: Science/Science.zip/gmt_os2.zip/src/grdedit.c

C/C++ Source or Header | 1995-03-13 | 4.8 KB | 179 lines

/*--------------------------------------------------------------------
 *    The GMT-system:    @(#)grdedit.c    2.14  3/13/95
 *
 *    Copyright (c) 1991-1995 by P. Wessel and W. H. F. Smith
 *    See README file for copying and redistribution conditions.
 *--------------------------------------------------------------------*/
/*
 * grdedit reads an existing grdfile and takes command line
 * arguments to redefine some of the grdheader parameters:
 *
 *    x_min/x_max OR x_inc (the other is recomputed)
 *    y_min/y_max OR y_inc (the other is recomputed)
 *    z_scale_factor/z_add_offset
 *    x_units/y_units/z_units
 *    title/command/remark
 *
 * Author:    Paul Wessel
 * Date:    9-JAN-1991-1995
 * Version:    2.0
 */

#include "gmt.h"

float *a;

main (argc, argv)
int argc;
char **argv; {
    int i, entry, one_or_zero, dummy[4];
    int error = FALSE, got_input = FALSE, got_region = FALSE, shift = FALSE;

    double w, e, s, n, shift_amount = 0.0;

    char *grdfile, input[512], *ptr;

    struct GRD_HEADER grd;

    input[0] = 0;
    grdfile = CNULL;
    w = e = s = n = 0.0;
    dummy[3] = dummy[2] = dummy[1] = dummy[0] = 0;

    argc = gmt_begin (argc, argv);

    for (i = 1; i < argc; i++) {
        if (argv[i][0] == '-') {
            switch (argv[i][1]) {
                /* Common parameters */

                case 'R':
                case '\0':
                    error += get_common_args (argv[i], &w, &e, &s, &n);
                    if (argv[i][1] == 'R') got_region = TRUE;
                    break;

                /* Supplemental parameters */

                case 'D':
                    strcpy (input, &argv[i][2]);
                    got_input = TRUE;
                    break;
                case 'S':
                    shift = TRUE;
                    break;
                default:
                    error = TRUE;
                    gmt_default_error (argv[i][1]);
                    break;
            }
        }
        else
            grdfile = argv[i];
    }

    if (argc == 1 || gmt_quick) {
        fprintf (stderr, "grdedit %s - Modifying the header in a netCDF grdfile\n\n", GMT_VERSION);
        fprintf (stderr, "usage: grdedit grdfile [-R<west>/<east>/<south>/<north>\n");
        fprintf (stderr, "    [-S] [-Dxunit/yunit/zunit/scale/offset/title/remark]\n");

        if (gmt_quick) exit (-1);

        fprintf (stderr, "    grdfile is file to be modified\n");
        fprintf (stderr, "\n\tOPTIONS:\n");
        fprintf (stderr, "    -D to enter information.  Specify '=' to get default value\n");
        explain_option ('R');
        fprintf (stderr, "    -S For global grids of 360 degree longitude range.\n");
        fprintf (stderr, "       Will rotate entire grid to coincide with new borders in -R\n");
        exit (-1);
    }

    if (shift && !got_region) {
        fprintf (stderr, "%s: GMT SYNTAX ERROR -S option:  Must also specify -R\n", gmt_program);
        error++;
    }
    if (shift && fabs (w - e) != 360.0) {
        fprintf (stderr, "%s: GMT SYNTAX ERROR -S option:  -R longitudes must span exactly 360 degrees\n", gmt_program);
        error++;
    }
    if (!grdfile) {
        fprintf (stderr, "%s: GMT SYNTAX ERROR:  Must specify input file\n", gmt_program);
        error++;
    }
    if (error) exit (-1);

    if (!strcmp (grdfile,  "=")) {
        fprintf (stderr, "grdedit: Piping of grdfile not supported!\n");
        exit (-1);
    }

    if (read_grd_info (grdfile, &grd)) {
        fprintf (stderr, "grdedit: Error opening file %s\n", grdfile);
        exit (-1);
    }

    if (shift && fabs (grd.x_max - grd.x_min) != 360.0) {
        fprintf (stderr, "grdedit: Shift only allowed for global grids\n");
        exit (-1);
    }

    /* Decode grd information given, if any */

    if (got_input) {
        ptr = strtok (input, "/");
        entry = 0;
        while (ptr) {
            switch (entry) {
                case 0:
                    if (ptr[0] != '=') strcpy (grd.x_units, ptr);
                    break;
                case 1:
                    if (ptr[0] != '=') strcpy (grd.y_units, ptr);
                    break;
                case 2:
                    if (ptr[0] != '=') strcpy (grd.z_units, ptr);
                    break;
                case 3:
                    if (ptr[0] != '=') grd.z_scale_factor = atof (ptr);
                    break;
                case 4:
                    if (ptr[0] != '=') grd.z_add_offset = atof (ptr);
                    break;
                case 5:
                    if (ptr[0] != '=') strcpy (grd.title, ptr);
                    break;
                case 6:
                    if (ptr[0] != '=') strcpy (grd.remark, ptr);
                    break;
                default:
                    break;
            }
            ptr = strtok (CNULL, "/");
            entry++;
        }
    }

    if (got_region && !shift) {
        one_or_zero = (grd.node_offset) ? 0 : 1;
        grd.x_min = w;    grd.x_max = e;
        grd.x_inc = (grd.x_max - grd.x_min) / (grd.nx - one_or_zero);
        grd.y_min = s;    grd.y_max = n;
        grd.y_inc = (grd.y_max - grd.y_min) / (grd.ny - one_or_zero);
    }

    if (shift) {
        shift_amount = w - grd.x_min;
        a = (float *) memory (CNULL, (int)(grd.nx * grd.ny), sizeof (float), "grdedit");
        read_grd (grdfile, &grd, a, 0.0, 0.0, 0.0, 0.0, dummy, FALSE);
        grd_shift (&grd, a, shift_amount);
        write_grd (grdfile, &grd, a, 0.0, 0.0, 0.0, 0.0, dummy, FALSE);
        free ((char *)a);
    }
    else if (write_grd_info (grdfile, &grd)) {
        fprintf (stderr, "grdedit: Error updating file %s\n", grdfile);
        exit (-1);
    }

    gmt_end (argc, argv);
}