cell_stats.c File Reference

#include "gis.h"
#include <stdlib.h>

Include dependency graph for cell_stats.c:

Go to the source code of this file.

Defines
#define	INCR   10
#define	SHIFT   6
#define	NODE   struct Cell_stats_node
Functions
int	G_init_cell_stats (struct Cell_stats *s)
	initialize cell stats
int	G_update_cell_stats (CELL *cell, int n, struct Cell_stats *s)
	add data to cell stats
int	G_find_cell_stat (CELL cat, long *count, struct Cell_stats *s)
	random query of cell stats
int	G_rewind_cell_stats (struct Cell_stats *s)
	reset/rewind cell stats
int	G_next_cell_stat (CELL *cat, long *count, struct Cell_stats *s)
	retrieve sorted cell stats
int	G_get_stats_for_null_value (long *count, struct Cell_stats *s)
	Get a number of null values from stats structure. Note: when reporting values which appear in a map using G_next_cell_stats(), to get stats for null, call G_get_stats_for_null_value() first, since G_next_cell_stats() does not report stats for null.
int	G_free_cell_stats (struct Cell_stats *s)
	free cell stats

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Define Documentation

#define INCR   10

Definition at line 4 of file cell_stats.c.

Referenced by G_init_cell_stats(), and G_update_cell_stats().

#define NODE   struct Cell_stats_node

Definition at line 9 of file cell_stats.c.

Referenced by G_init_cell_stats(), and G_update_cell_stats().

#define SHIFT   6

Definition at line 5 of file cell_stats.c.

Referenced by G_find_cell_stat(), G_next_cell_stat(), and G_update_cell_stats().

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Function Documentation

int G_find_cell_stat	(	CELL	cat,
		long *	count,
		struct Cell_stats *	s
	)

random query of cell stats

Allow finding the count for the NULL-value

Returns:

int

Definition at line 215 of file cell_stats.c.

References G_is_c_null_value(), and SHIFT.

int G_free_cell_stats

(

struct Cell_stats *

s

)

free cell stats

The memory associated with structure s is freed. This routine may be called any time after callingG_init_cell_stats.

Parameters:

s

Returns:

int

Definition at line 439 of file cell_stats.c.

int G_get_stats_for_null_value	(	long *	count,
		struct Cell_stats *	s
	)

Get a number of null values from stats structure. Note: when reporting values which appear in a map using G_next_cell_stats(), to get stats for null, call G_get_stats_for_null_value() first, since G_next_cell_stats() does not report stats for null.

Parameters:

	count
	s

Returns:

int

Definition at line 422 of file cell_stats.c.

int G_init_cell_stats

(

struct Cell_stats *

s

)

initialize cell stats

Set the count for NULL-values to zero.

Returns:

int

Definition at line 34 of file cell_stats.c.

References G_malloc(), INCR, and NODE.

int G_next_cell_stat	(	CELL *	cat,
		long *	count,
		struct Cell_stats *	s
	)

retrieve sorted cell stats

Do not return a record for the NULL-value

Returns:

int

Definition at line 358 of file cell_stats.c.

References if(), and SHIFT.

Referenced by G_cell_stats_histo_eq(), G_make_histogram_cs(), G_make_histogram_eq_colors(), G_make_histogram_log_colors(), and G_write_histogram_cs().

int G_rewind_cell_stats

(

struct Cell_stats *

s

)

reset/rewind cell stats

The structure s is rewound (i.e., positioned at the first raster category) so that sorted sequential retrieval can begin.

Parameters:

s

Returns:

int

Definition at line 284 of file cell_stats.c.

Referenced by G_cell_stats_histo_eq(), G_make_histogram_cs(), G_make_histogram_eq_colors(), G_make_histogram_log_colors(), and G_write_histogram_cs().

int G_update_cell_stats	(	CELL *	cell,
		int	n,
		struct Cell_stats *	s
	)

add data to cell stats

Look for NULLs and update the NULL-value count.

Returns:

int

Definition at line 67 of file cell_stats.c.

References cat, G_is_c_null_value(), G_realloc(), INCR, NODE, and SHIFT.

Referenced by G_put_map_row_random().

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