[GRASS-user] total Newbie help request

GRASS GRASS user
1

I’ve downloaded GRASS 6.3.0, and am running it on a MacBook Pro. I’ve downloaded the Spearfish data set and gotten it to work. BUT, and here’s the problem: I want to work with a shapefile (CORNELIUS_ddpolygons_None.shp) of an archaeological site consisting of a vector map of features. I have tried for 3 straight days to get the *&#%@ thing loaded and set up in a new location and cannot do it. The archaeological site is 715 feet EW by 230 feet NS. It is an X,Y map. I have also downloaded Neteler’s GRASS in a Nutshell tutorial and the one for GRASS 6.0, version 1.2 from Hannover. I have tried to follow the instructions and have not managed to get anything done.

Is it possible for some kind soul to give me step by step instructions so that I can see how it’s done and then hopefully be able to go from there?

Thanks in advance for considering,

Lyle Browning

2

On Sat, 2008-06-21 at 19:55 -0400, Lyle E. Browning wrote:

I've downloaded GRASS 6.3.0, and am running it on a MacBook Pro. I've
downloaded the Spearfish data set and gotten it to work. BUT, and
here's the problem: I want to work with a shapefile
(CORNELIUS_ddpolygons_None.shp) of an archaeological site consisting
of a vector map of features. I have tried for 3 straight days to get
the *&#%@ thing loaded and set up in a new location and cannot do it.
The archaeological site is 715 feet EW by 230 feet NS. It is an X,Y
map. I have also downloaded Neteler's GRASS in a Nutshell tutorial and
the one for GRASS 6.0, version 1.2 from Hannover. I have tried to
follow the instructions and have not managed to get anything done.

Is it possible for some kind soul to give me step by step instructions
so that I can see how it's done and then hopefully be able to go from
there?

Thanks in advance for considering,

Lyle Browning

Dear Lyle,

hopefully this will bring you further (I am not using a Mac - I just
assume it's the same like on a linux-box).

1. Open a terminal and launch grass in text-mode with "grass63 -text"

2. Name your LOCATION (e.g. "xy"), leave for the start the Mapset set to
PERMANENT and provide the path to where you want the LOCATION to be
created (that should be your GIS database). Finally hit "Esc+Enter".

3. Read the questions and answer (...yes in the first 2, choose "A",
confirm with yes, provide a description if you want, confirm)

4. Here you can ignore the settings about the extent of your location
and continue till you finally get into your GRASS session in your new
"xy" location.

5. Import your raster map with r.in.gdal and your shapefile with the
v.in.ogr module(s). Make sure to use the "-e" flag so the computational
region extents to the extent of your shapefile.

(example: v.in.ogr -e dsn=CORNELIUS_ddpolygons_None.shp
out=cornelius_dd)

*** If you would like to do that with the GUI type "gis.m" immediately
after you enter the "xy"location and look for the respective import
tools under File > Import raster (vector) map ***

Cheers,

Nikos

3

Lyle,

On Sun, Jun 22, 2008 at 1:55 AM, Lyle E. Browning <lebrowning@att.net> wrote:

I've downloaded GRASS 6.3.0, and am running it on a MacBook Pro. I've
downloaded the Spearfish data set and gotten it to work. BUT, and here's the
problem: I want to work with a shapefile (CORNELIUS_ddpolygons_None.shp) of
an archaeological site consisting of a vector map of features. I have tried
for 3 straight days to get the *&#%@ thing loaded and set up in a new
location and cannot do it. The archaeological site is 715 feet EW by 230
feet NS. It is an X,Y map.

What is precisely not working? Maybe you just have to zoom to the map
to see it? Possibly your current region is just elsewhere.

Markus

PS: (Un)related: In the GIS manager (gis.m) there is a georeferencing
tool (File > Georeference)
which helps you to geocode that vector map in case you need that.

4

On Sat, 2008-06-21 at 21:12 -0400, Lyle E. Browning wrote:
Sorry,

I forgot to cc to the list.

[...]

The error message is: v.in.ogr -e
dsn=CORNELIUS_ddpolygons_None. shp out=cornelius_dd
Sorry <shp> is not a valid option

[...]

Lyle,

a. I think that the 8000 pixels is too big. I don't really have any
prove for that. Just my small experience that files created with such a
resolution will be big and heavy for processing. If you don't really
need it you could reduce its size.

b. Yes you have either to give the full path of your shapefile or to
navigate in the subdirectory where your shapefile is located and run
form within it the v.in.ogr module.

In this "special" error you mention I think you have a "blank space"
between the filename and the extension ".shp". So the "dsn=" parameter
should NOT be like

"dsn=CORNELIUS_ddpolygons_None. shp"

but it should be like

"dsn=CORNELIUS_ddpolygons_None.shp"

Cheers,

Nikos

5

On Jun 22, 2008, at 3:38 AM, Nikos Alexandris wrote:

Lyle,

a. I think that the 8000 pixels is too big. I don't really have any
prove for that. Just my small experience that files created with such a
resolution will be big and heavy for processing. If you don't really
need it you could reduce its size.

I've reduced it to 750NS by 1000EW.

b. Yes you have either to give the full path of your shapefile or to
navigate in the subdirectory where your shapefile is located and run
form within it the v.in.ogr module.

Ah, I thought that once it created the permanent file, then the subfile, it would assign it to one or the other.

And that worked. I now have the map in there. The other thing, was that the 0,0 origin wasn't below and left of the lower left corner of the onscreen map (this was digitizing a scan of a map on graph paper done in the 1970's into Vectorworks). Once the shapefile was exported with the 0,0 origin correctly placed and the full path given, it is now shown on screen.

I figured it had to be some ignorance of syntax on my part as the Spearfish data worked and so it was. Thanks so much.

Lyle

In this "special" error you mention I think you have a "blank space"
between the filename and the extension ".shp". So the "dsn=" parameter
should NOT be like

"dsn=CORNELIUS_ddpolygons_None. shp"

but it should be like

"dsn=CORNELIUS_ddpolygons_None.shp"

Cheers,

Nikos