int get_range(const char *name, long *min, long *max)
{
struct Range range;
int nrows, ncols, row, col;
CELL *cell;
int fd;
CELL cmin, cmax;
struct Cell_head cellhd;
if (Rast_read_range(name, "", &range) < 0) {
Rast_init_range(&range); /* read the file to get the range */
Rast_get_cellhd(name, "", &cellhd);
Rast_set_window(&cellhd);
cell = Rast_allocate_c_buf();
fd = Rast_open_old(name, "");
nrows = Rast_window_rows();
ncols = Rast_window_cols();
G_message(_("Reading %s ..."), name);
for (row = 0; row < nrows; row++) {
G_percent(row, nrows, 2);
Rast_get_c_row_nomask(fd, cell, row);
for (col = 0; col < ncols; col++)
Rast_update_range(cell[col], &range);
}
G_percent(row, nrows, 2);
Rast_close(fd);
G_free(cell);
}
Rast_get_range_min_max(&range, &cmin, &cmax);
*min = cmin;
*max = cmax;
return 0;
}
void new_stats(const char *name, struct Reclass *reclass)
{
struct Histogram histo, histo2;
struct Range range;
CELL cat, cat2;
int i;
CELL min, max;
min = reclass->min;
max = reclass->max;
/* read histogram for original file */
G_suppress_warnings(1);
i = Rast_read_histogram(reclass->name, reclass->mapset, &histo);
G_suppress_warnings(0);
if (i <= 0)
return;
/* compute data rage for reclass */
Rast_init_range(&range);
for (i = 0; i < histo.num; i++) {
cat = histo.list[i].cat;
if (cat < min || cat > max)
continue;
cat2 = reclass->table[cat - min];
Rast_update_range(cat2, &range);
}
Rast_write_range(name, &range);
/* now generate a histogram from the original */
/* allocate histogram list */
histo2.num += range.max - range.min + 1;
histo2.list = (LIST *) G_calloc(histo2.num, sizeof(LIST));
/* set all counts to 0 */
i = 0;
for (cat = range.min; cat <= range.max; cat++) {
histo2.list[i].cat = cat;
histo2.list[i++].count = 0;
}
/* go thru original histogram and add into histo2 */
for (i = 0; i < histo.num; i++) {
cat = histo.list[i].cat;
if (cat < min || cat > max)
Rast_set_c_null_value(&cat, 1);
else
cat2 = reclass->table[cat - min];
if (!Rast_is_c_null_value(&cat))
histo2.list[cat2 - range.min].count += histo.list[i].count;
}
Rast_write_histogram(name, &histo2);
}
/*!
* \brief Construct default range
*
* Sets the integer range to [1,255]
*
* \param[out] r pointer to Range structure which holds range info
*/
void Rast_construct_default_range(struct Range *range)
{
Rast_update_range(DEFAULT_CELL_MIN, range);
Rast_update_range(DEFAULT_CELL_MAX, range);
}
/*!
* \brief Read raster range (CELL)
*
* This routine reads the range information for the raster map
* <i>name</i> in <i>mapset</i> into the <i>range</i> structure.
*
* A diagnostic message is printed and -1 is returned if there is an error
* reading the range file. Otherwise, 0 is returned.
*
* Old range file (those with 4 numbers) should treat zeros in this
* file as NULL-values. New range files (those with just 2 numbers)
* should treat these numbers as real data (zeros are real data in
* this case). An empty range file indicates that the min, max are
* undefined. This is a valid case, and the result should be an
* initialized range struct with no defined min/max. If the range file
* is missing and the map is a floating-point map, this function will
* create a default range by calling G_construct_default_range().
*
* \param name map name
* \param mapset mapset name
* \param[out] range pointer to Range structure which holds range info
*
* \return -1 on error
* \return 1 on success
* \return 2 if range is empty
* \return 3 if raster map is floating-point, get range from quant rules
*/
int Rast_read_range(const char *name, const char *mapset, struct Range *range)
{
FILE *fd;
CELL x[4];
char buf[200];
int n, count;
struct Quant quant;
struct FPRange drange;
Rast_init_range(range);
fd = NULL;
/* if map is not integer, read quant rules, and get limits */
if (Rast_map_type(name, mapset) != CELL_TYPE) {
DCELL dmin, dmax;
if (Rast_read_quant(name, mapset, &quant) < 0) {
G_warning(_("Unable to read quant rules for raster map <%s>"),
G_fully_qualified_name(name, mapset));
return -1;
}
if (Rast_quant_is_truncate(&quant) || Rast_quant_is_round(&quant)) {
if (Rast_read_fp_range(name, mapset, &drange) >= 0) {
Rast_get_fp_range_min_max(&drange, &dmin, &dmax);
if (Rast_quant_is_truncate(&quant)) {
x[0] = (CELL) dmin;
x[1] = (CELL) dmax;
}
else { /* round */
if (dmin > 0)
x[0] = (CELL) (dmin + .5);
else
x[0] = (CELL) (dmin - .5);
if (dmax > 0)
x[1] = (CELL) (dmax + .5);
else
x[1] = (CELL) (dmax - .5);
}
}
else
return -1;
}
else
Rast_quant_get_limits(&quant, &dmin, &dmax, &x[0], &x[1]);
Rast_update_range(x[0], range);
Rast_update_range(x[1], range);
return 3;
}
if (G_find_file2_misc("cell_misc", "range", name, mapset)) {
fd = G_fopen_old_misc("cell_misc", "range", name, mapset);
if (!fd) {
G_warning(_("Unable to read range file for <%s>"),
G_fully_qualified_name(name, mapset));
return -1;
}
/* if range file exists but empty */
if (!fgets(buf, sizeof buf, fd)) {
if (fd)
fclose(fd);
return 2;
}
x[0] = x[1] = x[2] = x[3] = 0;
count = sscanf(buf, "%d%d%d%d", &x[0], &x[1], &x[2], &x[3]);
/* if wrong format */
if (count <= 0) {
if (fd)
fclose(fd);
G_warning(_("Unable to read range file for <%s>"),
G_fully_qualified_name(name, mapset));
return -1;
}
for (n = 0; n < count; n++) {
/* if count==4, the range file is old (4.1) and 0's in it
have to be ignored */
if (count < 4 || x[n])
Rast_update_range((CELL) x[n], range);
}
fclose(fd);
}
return 1;
}
/*
* check_stats() - Check and update statistics
*
* RETURN: 0 on success / 1 on failure
*/
int check_stats(const char *name)
{
RASTER_MAP_TYPE data_type;
struct Histogram histogram;
struct Categories cats;
struct Range range;
struct FPRange fprange;
int i, histo_num;
int cats_ok;
int max;
data_type = Rast_map_type(name, "");
G_message(_("Updating statistics for [%s]..."), name);
if (!do_histogram(name))
return 1;
if (Rast_read_histogram(name, "", &histogram) <= 0)
return 1;
/* Init histogram range */
if (data_type == CELL_TYPE)
Rast_init_range(&range);
else
Rast_init_fp_range(&fprange);
G_message(_("Updating histogram range..."));
i = histo_num = Rast_get_histogram_num(&histogram);
while (i >= 0) {
G_percent(i, histo_num, 2);
if (data_type == CELL_TYPE)
Rast_update_range(Rast_get_histogram_cat(i--, &histogram), &range);
else
Rast_update_fp_range((DCELL) Rast_get_histogram_cat(i--, &histogram),
&fprange);
}
/* Write histogram range */
if (data_type == CELL_TYPE)
Rast_write_range(name, &range);
else
Rast_write_fp_range(name, &fprange);
/* Get category status and max */
cats_ok = (Rast_read_cats(name, "", &cats) >= 0);
max = (data_type == CELL_TYPE ? range.max : fprange.max);
/* Further category checks */
if (!cats_ok)
Rast_init_cats("", &cats);
else if (cats.num != max) {
cats.num = max;
cats_ok = 0;
}
/* Update categories if needed */
if (!cats_ok) {
G_message(_("Updating the number of categories for [%s]..."), name);
Rast_write_cats(name, &cats);
}
Rast_free_histogram(&histogram);
Rast_free_cats(&cats);
return 0;
}
