[GRASSLIST:5459] geogrid in ps.map

GRASS GRASS user
1

Hi all, I am using grass5.7 on osx (May 2004 or so) and I am trying to make a world mercator map using ps.map. I would like to add a geogrid, however the output only gives latitudinal lines, no longitudes. No errors were returned. The command I gave was

ps.map input=- output=test.eps -e
geogrid 30 d
color black
numbers 1
end

g.region -p yields

projection: 99 (Mercator)
zone: 0
datum: ** unknown (default: WGS84) **
ellipsoid: wgs84
north: 11714654.84
south: -11714654.84
west: -20037508.34
east: 20037508.34
nsres: 3697.80771465
ewres: 3710.64969259
rows: 6336
cols: 10800

Alternatively, I have also tried to import (using v.proj) a worldwide vector grid with 30 degree spacing, however every attempt to import yields in errors such as (using grass 5.3):

Input Projection Parameters: +proj=latlong +a=6378137 +es=0.006694379990141316 +towgs84=0.000,0.000,0.000

Output Projection Parameters: +proj=merc +lat_ts=0.0000000000 +lon_0=180.0000000000 +k_0=1.0000000000 +a=6378137 +es=0.006694379990141316

Creating dig file...
pj_transform() failed
cause: latitude or longitude exceeded limits
Error in pj_do_proj

OR (using 5.7)

v.proj input=grid30 location=latlong_wgs84

Input Projection Parameters: +proj=latlong +a=6378137 +rf=298.257223563 +no_defs +towgs84=0.000,0.000,0.000
Input Unit Factor: 1

Output Projection Parameters: +proj=merc +lat_ts=0.0000000000 +lon_0=180.0000000000 +k_0=1.0000000000 +a=6378137 +rf=298.257223563 +no_defs
Output Unit Factor: 1

Creating vector file...
Building topology ...
Registering lines:

At this point v.proj stops running. Trying to display the vector with yields:

GRASS 5.7.0:~ > d.vect grid30
WARNING: coor files of vector 'grid30@ianmacmillan' is larger than it
          should be (14312 bytes excess).
WARNING: Cannot display areas, topology not available

I think there is a problem with worldwide mercator projections, but I can't figure what it is. Displaying other worldwide data (I can't remember how I got it into this location in the first place) shows that the region is appropriate for a world map. It is hard to tell for sure though since units are measured in meters.

Any ideas?

Thanks,
Ian

2

Ian,

This is way out of date, given that 5.7 (now 6.0.0 beta 1) is the rapid
development version. MANY changes and fixes have been implemented since last
May.

Given that you are using a Mac, I highly recommend you get Lorenzo Moretti's
binaries and install them. Install the new libraries and GRASS 6.0.0 beta1.

Make sure that you delete any old copies of gdal and proj4 libraries and
utilities you may have in /usr/local/bin and /usr/local/lib. These can
confuse Moretti's binaries that use very new versions of both utilities and
keeps them in /usr/local/grasslib/bin and /usr/local/grasslib/lib. Also make
sure that /usr/local/grasslib/bin is in your path to make life easier.

Hope this solves your issues.

Michael

On 1/20/05 12:44 PM, "Ian MacMillan" <ian_macmillan@umail.ucsb.edu> wrote:

Hi all, I am using grass5.7 on osx (May 2004 or so) and I am trying to
make a world mercator map using ps.map. I would like to add a geogrid,
however the output only gives latitudinal lines, no longitudes. No
errors were returned. The command I gave was

ps.map input=- output=test.eps -e
geogrid 30 d
color black
numbers 1
end
end

g.region -p yields

projection: 99 (Mercator)
zone: 0
datum: ** unknown (default: WGS84) **
ellipsoid: wgs84
north: 11714654.84
south: -11714654.84
west: -20037508.34
east: 20037508.34
nsres: 3697.80771465
ewres: 3710.64969259
rows: 6336
cols: 10800

Alternatively, I have also tried to import (using v.proj) a worldwide
vector grid with 30 degree spacing, however every attempt to import
yields in errors such as (using grass 5.3):

Input Projection Parameters: +proj=latlong +a=6378137
+es=0.006694379990141316 +towgs84=0.000,0.000,0.000

Output Projection Parameters: +proj=merc +lat_ts=0.0000000000
+lon_0=180.0000000000 +k_0=1.0000000000 +a=6378137
+es=0.006694379990141316

Creating dig file...
pj_transform() failed
cause: latitude or longitude exceeded limits
Error in pj_do_proj

OR (using 5.7)

v.proj input=grid30 location=latlong_wgs84

Input Projection Parameters: +proj=latlong +a=6378137 +rf=298.257223563
+no_defs +towgs84=0.000,0.000,0.000
Input Unit Factor: 1

Output Projection Parameters: +proj=merc +lat_ts=0.0000000000
+lon_0=180.0000000000 +k_0=1.0000000000 +a=6378137 +rf=298.257223563
+no_defs
Output Unit Factor: 1

Creating vector file...
Building topology ...
Registering lines:

At this point v.proj stops running. Trying to display the vector with
yields:

GRASS 5.7.0:~ > d.vect grid30
WARNING: coor files of vector 'grid30@ianmacmillan' is larger than it
          should be (14312 bytes excess).
WARNING: Cannot display areas, topology not available

I think there is a problem with worldwide mercator projections, but I
can't figure what it is. Displaying other worldwide data (I can't
remember how I got it into this location in the first place) shows that
the region is appropriate for a world map. It is hard to tell for sure
though since units are measured in meters.

Any ideas?

Thanks,
Ian

______________________________
Michael Barton, Professor of Anthropology
School of Human Evolution and Social Change
Arizona State University
Tempe, AZ 85287-2402
USA

voice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton