[GRASS-dev] Re: [GRASS GIS] #489: g.setproj: sets proj info with missing UTM zone

[GRASS GIS]

#489: g.setproj: sets proj info with missing UTM zone
----------------------+-----------------------------------------------------
  Reporter:  hamish   |       Owner:  grass-dev at lists.osgeo.org
      Type:  defect   |      Status:  new                      
  Priority:  minor    |   Milestone:  6.4.0                    
 Component:  default  |     Version:  6.4.0 RCs                
Resolution:           |    Keywords:  g.setproj                
  Platform:  Linux    |         Cpu:  x86-32                   
----------------------+-----------------------------------------------------
Old description:

> Hi,
>
> with g.setproj it is possible to set the region so that the resulting
> PROJ_INFO file is missing the zone: field. Perhaps
> this is because 'g.region -p' says the zone is -55 while g.proj
> had 55(S)?
>
> {{{
> G640rc2> g.setproj
> ...
> Would you still like to change some of the parameters?(y/n) [n] y
> WARNING: Zone in default geographic region definition: -55
>          is different from zone in PROJ_INFO file: 55
> ...
> Please specify projection name
> >utm
> }}}
> [ do we want a space after the '>' prompt? ]
> {{{
> Do you wish to specify a geodetic datum for this location?(y/n) [y] y
>
> Please specify datum name
> >custom
> }}}
> [I did want the datum to be Australia GD 1994, but that's not a choice]
> {{{
> Please specify ellipsoid name
> >grs80
>
> Please specify datum transformation parameters
> >towgs84=0,0,0
>
> Parameters to be used are:
> "towgs84=0,0,0"
> Is this correct?(y/n) [y] y
> South Hemisphere(y/n) [n] y
> The UTM zone is now set to 55
> Do you want to change the UTM zone?(y/n) [n] n
> UTM zone information has not been updated
>
> Projection information has been recorded for this location
> }}}
>
> then
>
> {{{
>  g.proj -p
> -PROJ_INFO-------------------------------------------------
> name       : Universe Transverse Mercator
> towgs84    : 0,0,0
> proj       : utm
> ellps      : grs80
> a          : 6378137.0000000000
> es         : 0.0066943800
> f          : 298.2572221010
> south      : defined
> -PROJ_UNITS------------------------------------------------
> unit       : meter
> units      : meters
> meters     : 1.0
> }}}
>
> and then r.in.gdal segfaults when attempting the matching proj settings
> comparison. (strcmp() missing key value in lib/gis/make_loc.c)
>

> Hamish

New description:

 Hi,

 with g.setproj it is possible to set the region so that the resulting
 PROJ_INFO file is missing the zone: field. Perhaps
 this is because 'g.region -p' says the zone is -55 while g.proj
 had  ?

 {{{
 G640rc2> g.setproj
 ...
 Would you still like to change some of the parameters?(y/n) [n] y
 WARNING: Zone in default geographic region definition: -55
          is different from zone in PROJ_INFO file: 55
 ...
 Please specify projection name
 >utm
 }}}
 [ do we want a space after the '>' prompt? ]
 {{{
 Do you wish to specify a geodetic datum for this location?(y/n) [y] y

 Please specify datum name
 >custom
 }}}
 [I did want the datum to be Australia GD 1994, but that's not a choice]
 {{{
 Please specify ellipsoid name
 >grs80

 Please specify datum transformation parameters
 >towgs84=0,0,0

 Parameters to be used are:
 "towgs84=0,0,0"
 Is this correct?(y/n) [y] y
 South Hemisphere(y/n) [n] y
 The UTM zone is now set to 55
 Do you want to change the UTM zone?(y/n) [n] n
 UTM zone information has not been updated

 Projection information has been recorded for this location
 }}}

 then

 {{{
  g.proj -p
 -PROJ_INFO-------------------------------------------------
 name       : Universe Transverse Mercator
 towgs84    : 0,0,0
 proj       : utm
 ellps      : grs80
 a          : 6378137.0000000000
 es         : 0.0066943800
 f          : 298.2572221010
 south      : defined
 -PROJ_UNITS------------------------------------------------
 unit       : meter
 units      : meters
 meters     : 1.0
 }}}

 and then r.in.gdal segfaults when attempting the matching proj settings
 comparison. (strcmp() missing key value in lib/gis/make_loc.c)


 Hamish

Comment (by neteler):

 The code chunk in general/g.setproj/main.c (see
 [source:grass/branches/develbranch_6/general/g.setproj/main.c#L413]) is:
 {{{
             if (parm->ask) {
                 if (G_strcasecmp(desc->type, "bool") == 0) {
                     if (G_yes((char *)desc->desc, 0)) {
                         G_set_key_value(desc->key, "defined",
 out_proj_keys);
                         if (G_strcasecmp(parm->name, "SOUTH") == 0)
                             cellhd.zone = -abs(cellhd.zone);
                     }
                 }
 }}}


 and in lib/proj/get_proj.c it is (line 154)
 {{{
             /* if zone is negative, write abs(zone) and define south */
             info->zone = -info->zone;
 }}}

 So it seems to be valid?

-- 
Ticket URL: <http://trac.osgeo.org/grass/ticket/489#comment:1>
GRASS GIS <http://grass.osgeo.org>