GRASS GIS 8 Programmer's Manual  8.4.0dev(2024)-6c790bf5c0
adj_cellhd.c File Reference

GIS Library - CELL header adjustment. More...

#include <math.h>
#include <string.h>
#include <grass/gis.h>
#include <grass/glocale.h>
Include dependency graph for adj_cellhd.c:

Go to the source code of this file.

Macros

#define LL_TOLERANCE   10
 

Functions

void G_adjust_Cell_head (struct Cell_head *cellhd, int row_flag, int col_flag)
 Adjust cell header. More...
 
void G_adjust_Cell_head3 (struct Cell_head *cellhd, int row_flag, int col_flag, int depth_flag)
 Adjust cell header for 3D values. More...
 
int G_adjust_window_ll (struct Cell_head *cellhd)
 Adjust window for lat/lon. More...
 

Detailed Description

GIS Library - CELL header adjustment.

(C) 2001-2009 by the GRASS Development Team

This program is free software under the GNU General Public License (>=v2). Read the file COPYING that comes with GRASS for details.

Author
Original author CERL

Definition in file adj_cellhd.c.

Macro Definition Documentation

◆ LL_TOLERANCE

#define LL_TOLERANCE   10

Definition at line 19 of file adj_cellhd.c.

Function Documentation

◆ G_adjust_Cell_head()

void G_adjust_Cell_head ( struct Cell_head cellhd,
int  row_flag,
int  col_flag 
)

Adjust cell header.

This function fills in missing parts of the input cell header (or region). It also makes projection-specific adjustments. The cellhd structure must have its north, south, east, west, and proj fields set.

If row_flag is true, then the north-south resolution is computed from the number of rows in the cellhd structure. Otherwise the number of rows is computed from the north-south resolution in the structure, similarly for col_flag and the number of columns and the east-west resolution.

Note: 3D values are not adjusted.

Parameters
[in,out]cellhdpointer to Cell_head structure
row_flagcompute n-s resolution
col_flagcompute e-w resolution

Definition at line 51 of file adj_cellhd.c.

References _, Cell_head::cols, Cell_head::ew_res, G_fatal_error(), Cell_head::north, Cell_head::ns_res, Cell_head::proj, PROJECTION_LL, Cell_head::rows, and Cell_head::south.

◆ G_adjust_Cell_head3()

void G_adjust_Cell_head3 ( struct Cell_head cellhd,
int  row_flag,
int  col_flag,
int  depth_flag 
)

Adjust cell header for 3D values.

This function fills in missing parts of the input cell header (or region). It also makes projection-specific adjustments. The cellhd structure must have its north, south, east, west, and proj fields set.

If row_flag is true, then the north-south resolution is computed from the number of rows in the cellhd structure. Otherwise the number of rows is computed from the north-south resolution in the structure, similarly for col_flag and the number of columns and the east-west resolution.

If depth_flag is true, top-bottom resolution is calculated from depths. If depth_flag are false, number of depths is calculated from top-bottom resolution.

Warning
This function can cause segmentation fault without any warning when it is called with Cell_head top and bottom set to zero.
Parameters
[in,out]cellhdpointer to Cell_head structure
row_flagcompute n-s resolution
col_flagcompute e-w resolution
depth_flagcompute t-b resolution

Definition at line 163 of file adj_cellhd.c.

References _, Cell_head::cols, Cell_head::cols3, Cell_head::depths, Cell_head::ew_res, Cell_head::ew_res3, G_fatal_error(), Cell_head::north, Cell_head::ns_res, Cell_head::ns_res3, Cell_head::proj, PROJECTION_LL, Cell_head::rows, Cell_head::rows3, Cell_head::south, and Cell_head::tb_res.

◆ G_adjust_window_ll()

int G_adjust_window_ll ( struct Cell_head cellhd)

Adjust window for lat/lon.

This function tries to automatically fix fp precision issues and adjust rounding errors for lat/lon.

Note: 3D values are not adjusted.

Parameters
[in,out]cellhdpointer to Cell_head structure
Returns
1 if window was adjusted
0 if window was not adjusted

Definition at line 552 of file adj_cellhd.c.

References _, Cell_head::east, Cell_head::ew_res, G_fatal_error(), G_lat_format(), G_lat_scan(), G_llres_format(), G_llres_scan(), G_lon_format(), G_lon_scan(), Cell_head::north, Cell_head::ns_res, Cell_head::proj, PROJECTION_LL, Cell_head::south, and Cell_head::west.