Re: [GRASS-user] Question about r.in.xyz

[Franz Schiller]

Hi Hamish


that's simply a function of what's present in your input data.
> for floating point values it will just be the next highest
> integer beyond the maximum data value and can be ignored.
>
> Uhm but it has to do with the "number of categores"? It's used for
Histogram only?


> see also the output of r.univar and the display histogram tool.
>
> Ok r.univar is ok (I guess).



>
> > - and in the r.info v2 I get a command slightly different from
> > the one I typed:
> > r.in.xyz input="C:\Test_areas\graphbased\saidav2" \
> >   output="v...@permanent" method="mean" type="FCELL" fs=" " \
> >   x=1 y=2 z=3 zscale=1.0 percent=100
> > Why?
>
> But it didn't change my dataset right?

Franz
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[GRASS-user] Use of r.mode

[Monica Buescu]

Greetings

This new topic is related with


I need to calculate mode for a base map that is composed by float values.
r.mode base=b...@permanent cover=1107...@permanent output=saida


And I get:
ERROR: reading r.stats output
ERROR: No rules specified

This means that I'm not being able to apply this function just because my
base map is a Float. Any ideas of how to fix this?

Thanks
Monica
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[GRASS-user] v.out.vtk and openGL limitation

[Pierluigi De Rosa]

Dear List,

I have a problem exporting a TIN using v.out.vtk
When the vtk file is done inside paraview I have problem because the
North Coordinates are bigger than 100 so i tried to use the -c flag
but the vtk I have as output seem to the the same I have without -c flag

Where I'm wrong?
thanks
Pierluigi

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Re: [GRASS-user] Type of data to be used in i.maxlik

[Kim Besson]

Hi Markus


> The input can be double but will be read as integer (CELL) since the
> function
> G_open_cell_old() is used [1].
>
> This means what? That pixels with values >255 are all the same? or pixels
like 1,034 and 2,043 are rounded?

Thanks
Kim
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[GRASS-user] Re: grass-user Digest, Vol 54, Issue 39

[bharath s]

hello,
i want to patch the two scenes of adjacent land sat( 146-37
,146-38 ) images.. The second image contains some part of 1st image also so
if i patch , is the duplicate data exist are not ? please help me Or is
there any another method to mosaic two images??
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[GRASS-user] Re: grass-user Digest, Vol 54, Issue 39

[Markus Neteler]

On Tue, Oct 19, 2010 at 10:40 AM, bharath s  wrote:
>
> hello,
>     i want to patch the two scenes of adjacent land sat( 146-37
> ,146-38 ) images.. The second image contains some part of 1st image also so
> if i patch , is the duplicate data exist are not ? please help me Or is
> there any another method to mosaic two images??


See
http://grass.osgeo.org/grass64/manuals/html64_user/r.patch.html

-> "The first name listed in the string input=name,name,name, ... is the name
 of the first map whose data values will be used to fill in "no
data" cells in the
 current region. The second through last input name maps will be
used, in order,
 to supply data values for for the remaining "no data" cells. "

Markus
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[GRASS-user] output file location

[Sandile Gumede]

Hello

Where do I get the output file which contains all the output for the script
below, the actual file name under my Mapset?

--
#!/bin/sh

#variable to customize:
# path to GRASS software main directory
GISBASE=/usr/lib/grass
# path to GRASS database
GISDBASE=$HOME/grassgis

LOCATION_NAME=SRTMDEM
MAPSET=PERMANENT

# nothing to change below
MAP=$1
LOCATION=$2


# generate temporal LOCATION:
TEMPDIR=FLOODS
mkdir -p $GISDBASE/$LOCATION_NAME/$MAPSET

# save existing $HOME/.grassrc6
if test -e $HOME/.grassrc6 ; then
mv $HOME/.grassrc6 /tmp/$TEMPDIR.grassrc6
fi

echo "LOCATION_NAME: $LOCATION_NAME" > $HOME/.grassrc6
echo "MAPSET:$MAPSET">> $HOME/.grassrc6
echo "DIGITIZER: none"   >> $HOME/.grassrc6
echo "GISDBASE: $GISDBASE"   >> $HOME/.grassrc6
export GISBASE=$GISBASE

# Create a WIND file with minimal information and no projection:
echo "proj: 3
zone:   0
north:  1
south:  0
east:   1
west:   0
cols:   1
rows:   1
e-w resol:  1
n-s resol:  1
top:1
bottom: 0
cols3:  1
rows3:  1
depths: 1
e-w resol3: 1
n-s resol3: 1
t-b resol:  1
" > $GISDBASE/$LOCATION_NAME/$MAPSET/WIND

# Copy WIND-file to DEFAULT_WIND:
cp $GISDBASE/$LOCATION_NAME/$MAPSET/WIND \
 $GISDBASE/$LOCATION_NAME/$MAPSET/DEFAULT_WIND


echo "name:  Latitude-Longitude
datum:   wgs84
towgs84: 0.000,0.000,0.000
proj:ll
ellps: wgs84
"> $GISDBASE/$LOCATION_NAME/$MAPSET/PROJ_INFO

echo "unit: degree
ubits:  degrees
meters: 1.0
"> $GISDBASE/$LOCATION_NAME/$MAPSET/PROJ_UNITS



export PATH=$GISBASE/bin:$GISBASE/scripts:$PATH
export LD_LIBRARY_PATH=$GISBASE/lib:$LD_LIBRARY_PATH
export GIS_LOCK=$$
export GISRC=$HOME/.grassrc6


# this should print GRASS version used:
g.version
# other calculations go here

# import rainfall data set.
 cd $HOME/grassgis



# DEM and Rainfall data sets.
r.in.gdal --o input=$HOME/grassgis/dem1.tif output=dem1
# r.in.gdal --o input=$HOME/grassgis/dem2.tif output=dem2
# r.in.gdal --o input=$HOME/grassgis/dem3.tif output=dem3
# r.in.gdal --o input=$HOME/grassgis/dem4.tif output=dem4
r.in.gdal --o input=$HOME/grassgis/Rainfall.tif output=rainfall

# set region resolution to be the dem
g.region rast=dem1 -p

# create MASK to the dem
r.mask input=d...@permanent 'maskcats=1 thru 1'

# calculate rainfall resolution to be the dem resolution.
r.mapcalculator amap=rainfall formula=A*1.0 help=- outfile=rain1

# creating set of maps indicating flow acc, drainage dir, streams
r.watershed --o elevation=d...@permanent drainage=flow1_direction
basin=catch1 stream=str1 accumulation=acc1 threshold=1000

# convert catch raster to polygon vector
r.to.vect in=catch1 out=catchments1 feature=area

# Calculate univariate statistics
v.rast.stats vector=catchments1 raster=rain1 colpre=precip

# view results
v.info -c catchments1
v.db.select catchments1

# remove existing mask
r.mask -r input=d...@permanent 'maskcats=1 thru 1'
-

-- 
Kind Regards
TS Gumede | CSIR | Meraka Institute | ICT4EO Research Group
Office Tel: 012 841 2606 | mobile : 072 258 1650
*"Work like a slave in order to live like a King" ~ Unknown*
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Re: [GRASS-user] d.grid fails with -g flag in winGRASS

[Markus Neteler]

On Wed, Oct 13, 2010 at 12:58 PM, Luigi Ponti  wrote:
> Hi there,
>
> Working on Win7 with today's binary snapshot WinGRASS-6.4.SVN-r43880 in
> North Caroline location. Issuing the following command (either via Cmd> text
> box or the button in the wxGUI):
>
>   d.grid  -g size=0.01
>
> triggers an error pop up saying:
>
>   Execution failed: 'd.grid  -g size=0.01 --q'
>   Details:
>   Error: Unable to set up lat/long projection parameters
>
> While the following:
>
>   d.grid  -w size=0.01
>
> works fine.
>
> Anybody experiencing the same error?

for the record: I have added a comment in your ticket
http://trac.osgeo.org/grass/ticket/1197

Markus
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Re: [GRASS-user] output file location

[Micha Silver]

Sandile Gumede wrote:


Hello

Where do I get the output file which contains all the output for the 
script below, the actual file name under my Mapset?


Maps output by GRASS are part of the GRASS database. Each vector or 
raster is not a single file, but rather a directory which contains 
several files. Each vector map has a directory under 
$LOCATION_NAME/$MAPSET/vector/ and it might also have a dbf entry or an 
sqlite table for attributes. The parts of a raster map are split among a 
few directories: $LOCATION_NAME/$MAPSET/cats , 
$LOCATION_NAME/$MAPSET/cell , $LOCATION_NAME/$MAPSET/hist etc.


--
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Re: [GRASS-user] Use of r.mode

[Micha Silver]

Monica Buescu wrote:


Greetings

This new topic is related with 



I need to calculate mode for a base map that is composed by float values.
r.mode base=b...@permanent cover=1107...@permanent output=saida   



And I get:
ERROR: reading r.stats output
ERROR: No rules specified

This means that I'm not being able to apply this function just because 
my base map is a Float. Any ideas of how to fix this?

How about r.mapcalc base_integer=int(base) ?

The base map should be integer (category ) values, where the mode is 
calculated for all cells with the same cat value, so it indeed should be 
an integer raster.




Thanks
Monica

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[GRASS-user] output file location

[Sandile Gumede]

Hi

Thanks, for grass module v.rast.stats vect=catchments1 rast=rain1
colpre=precip , is it the output file that I'm looking for in the path
below? If so which program is used to open it, I'm using ubuntu 9.04, my
default GRASS database is DBMF

$LOCATION_NAME/$MAPSET/dbf/catchments1.dbf

On Tue, Oct 19, 2010 at 2:52 PM, Micha Silver  wrote:

> Sandile Gumede wrote:
>
>  Hello
>>
>> Where do I get the output file which contains all the output for the
>> script below, the actual file name under my Mapset?
>>
>>  Maps output by GRASS are part of the GRASS database. Each vector or
> raster is not a single file, but rather a directory which contains several
> files. Each vector map has a directory under $LOCATION_NAME/$MAPSET/vector/
> and it might also have a dbf entry or an sqlite table for attributes. The
> parts of a raster map are split among a few directories:
> $LOCATION_NAME/$MAPSET/cats , $LOCATION_NAME/$MAPSET/cell ,
> $LOCATION_NAME/$MAPSET/hist etc.
>
> --
> Micha
>



-- 
Kind Regards
TS Gumede | CSIR | Meraka Institute | ICT4EO Research Group
Office Tel: 012 841 2606 | mobile : 072 258 1650
*"Work like a slave in order to live like a King" ~ Unknown*
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Re: [GRASS-dev] Re: [GRASS-user] v.db.join script

[Micha Silver]

Moritz Lennert wrote:


On 13/10/10 22:23, Micha Silver wrote:

One line from the v.db.join script uses grep and cut to get the column
names and the next line gets the column types like so:

db.describe -c bike_rides2 | grep '^Column' | cut -d ':' -f 3
INTEGER
CHARACTER
INTEGER
CHARACTER
CHARACTER
CHARACTER
CHARACTER

So the column size is actually ignored.

Next, in the script the above output is used by v.db.addcol to create
the new columns in the joined vector. So all new character columns are
created as a single char and the actual length is never used.

Questions:
Is the db.describe output the same for all db drivers?
Any suggestions how to fix this as a script?


Why not use an SQL join, i.e. something like the following ?

1) CREATE TABLE temp AS (SELECT * FROM $maptable JOIN $otable ON 
$column=$ocolumn)


2) rename table $maptable to something else

3) rename table temp to $maptable

4) if this works, remove the original $maptable

Interesting. So your suggestion is to run the above sql commands thru 
db.execute to create a new attribute table for an existing vector?



Not tested, but might be a more elegant solution ?

Moritz

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[GRASS-user] Re: output file location

[Micha Silver]

Sandile Gumede wrote:


Hi

Thanks, for grass module v.rast.stats vect=catchments1 rast=rain1 
colpre=precip , is it the output file that I'm looking for in the path 
below? If so which program is used to open it, I'm using ubuntu 9.04, 
my default GRASS database is DBMF


$LOCATION_NAME/$MAPSET/dbf/catchments1.dbf


If you're looking for only the attribute table, then yes, that's the file.
You can open it with OpenOffice Calc. Also you can see the whole table 
and export to a text file with v.db.select catchments1.


On Tue, Oct 19, 2010 at 2:52 PM, Micha Silver > wrote:


Sandile Gumede wrote:

Hello

Where do I get the output file which contains all the output
for the script below, the actual file name under my Mapset?

Maps output by GRASS are part of the GRASS database. Each vector
or raster is not a single file, but rather a directory which
contains several files. Each vector map has a directory under
$LOCATION_NAME/$MAPSET/vector/ and it might also have a dbf entry
or an sqlite table for attributes. The parts of a raster map are
split among a few directories: $LOCATION_NAME/$MAPSET/cats ,
$LOCATION_NAME/$MAPSET/cell , $LOCATION_NAME/$MAPSET/hist etc.

--
Micha




--
Kind Regards
TS Gumede | CSIR | Meraka Institute | ICT4EO Research Group
Office Tel: 012 841 2606 | mobile : 072 258 1650
/"Work like a slave in order to live like a King" ~ Unknown/


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[GRASS-user] r.reclass with floating point result

[Hanlie Pretorius]

Hi,

I'm trying to reclassify a raster with these categories:

|#|description
|-
|1|Sandy Loam
|2|Sandy Clay Loam
|*|no data


To this:
|#|description
|-
|1|32.7
|2|3
|*|no data

So, I use a text file with the followin rules:
1 = 32.7
2 = 3

And the command
r.reclass --overwrite input=c83a_soils
output=c83a_soils_infiltration_mm_per_3_hours
rules=infiltration_reclass_mm3hr.txt title=Saturated infiltration rate
in mm per 3 hours
33.20 rounded up to 33
(Tue Oct 19 15:46:10 2010) Command finished (1 sec)

The result is a raster with:
| #|description
|-
| 3|
|33|
| *|no data

I have also tried a rule file that says:
1 = 32.7 Sandy Loam
2 = 3 Sandy Clay Loam

With the result
| #|description
|-
| 3|Sandy Clay Loam
|33|Sandy Loam
| *|no data


So, I have two problems here: 1) I can't get r.reclass to output an
FCELL raster even though its help file suggest that only the input
file needs to be a CELL raster.
2) I don't understand how r.reclass uses the rules file.

Can someone perhaps help me?

Thanks
Hanlie
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Re: [GRASS-user] Use of r.mode

[Monica Buescu]

Hi Mich
Thanks for the reply. I think it has worked but everytime I try to open, my
winGRASS goes "bananas".
Just to sum what I have done
1- Import a xyz ASCII file that is a float with a range of [166297.00 -
20855944.0] (not all values are used) and Rows: 4655 ;Columns:
 4520  .
2- I did r.mapcalc int() to this file that gets the range of [166297
 20855944].
QUESTION: can I apply int to a FLoat with values as big as this?
3- I did r.mode base=int_base coverage= 1107...@permanent (it's a
high-resolution image) output=output1

Ok it runs (it takes some time as expected)
Thern if I try to display it freezes... Even If I just try r.info output1 it
also freezes.

Any thoughts aboutt this? (Thanks Micha)

On Tue, Oct 19, 2010 at 2:14 PM, Micha Silver  wrote:

> Monica Buescu wrote:
>
>  Greetings
>>
>> This new topic is related with
>>
>> I need to calculate mode for a base map that is composed by float values.
>> r.mode base=b...@permanent cover=1107...@permanent output=saida
>>
>> And I get:
>> ERROR: reading r.stats output
>> ERROR: No rules specified
>>
>> This means that I'm not being able to apply this function just because my
>> base map is a Float. Any ideas of how to fix this?
>>
> How about r.mapcalc base_integer=int(base) ?
>
> The base map should be integer (category ) values, where the mode is
> calculated for all cells with the same cat value, so it indeed should be an
> integer raster.
>
>
>> Thanks
>> Monica
>>
>> This mail was received via Mail-SeCure System.
>> 
>>
>> ___
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>>
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>>
>>
>>
>>
>
>
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Re: [GRASS-dev] Re: [GRASS-user] v.db.join script

[Moritz Lennert]

On 19/10/10 15:23, Micha Silver wrote:

Moritz Lennert wrote:


On 13/10/10 22:23, Micha Silver wrote:

One line from the v.db.join script uses grep and cut to get the column
names and the next line gets the column types like so:

db.describe -c bike_rides2 | grep '^Column' | cut -d ':' -f 3
INTEGER
CHARACTER
INTEGER
CHARACTER
CHARACTER
CHARACTER
CHARACTER

So the column size is actually ignored.

Next, in the script the above output is used by v.db.addcol to create
the new columns in the joined vector. So all new character columns are
created as a single char and the actual length is never used.

Questions:
Is the db.describe output the same for all db drivers?
Any suggestions how to fix this as a script?


Why not use an SQL join, i.e. something like the following ?

1) CREATE TABLE temp AS (SELECT * FROM $maptable JOIN $otable ON
$column=$ocolumn)

2) rename table $maptable to something else

3) rename table temp to $maptable

4) if this works, remove the original $maptable


Interesting. So your suggestion is to run the above sql commands thru
db.execute to create a new attribute table for an existing vector?


Yes. You could put them all into a temporary text file then send this 
file as one transaction to db.execute.


Moritz
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Re: [GRASS-user] r.reclass with floating point result

[Glynn Clements]

Hanlie Pretorius wrote:

> So, I have two problems here: 1) I can't get r.reclass to output an
> FCELL raster even though its help file suggest that only the input
> file needs to be a CELL raster.

A reclass table maps integers to integers. You cannot generate a
floating-point map by reclassing.

-- 
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Re: [GRASS-user] Use of r.mode

[Micha Silver]

On 10/19/2010 04:03 PM, Monica Buescu wrote:

Hi Mich
Thanks for the reply. I think it has worked but everytime I try to 
open, my winGRASS goes "bananas".

Hope you get some whipped cream with that ;-)


Just to sum what I have done
1- Import a xyz ASCII file that is a float with a range of [166297.00 
- 20855944.0] (not all values are used) and Rows: 4655 
;Columns:  4520  .


About 20,000,000 cells. That should be OK.
Do you know how many different values are actually in the data?
2- I did r.mapcalc int() to this file that gets the range of [166297 
 20855944].

QUESTION: can I apply int to a FLoat with values as big as this?
An integer raster is represented by 32 bit signed integer values i.e. 
from (about) -2 billion to +2 billion. So you're OK here.


3- I did r.mode base=int_base coverage= 1107...@permanent (it's a 
high-resolution image) output=output1


Ok it runs (it takes some time as expected)
Thern if I try to display it freezes... Even If I just try r.info 
 output1 it also freezes.


I'd try two things here. First can you change to a smaller region and 
rerun r.mode and try to display the results?
Second: the result of r.mode is a "reclass" of the original values. So I 
suppose it has to be recalculated each time you want to display. You can 
make that reclass map into a permanent raster by running:

r.mapcalc "output2 = output1"
Then try displaying the output2.


Any thoughts aboutt this? (Thanks Micha)

On Tue, Oct 19, 2010 at 2:14 PM, Micha Silver > wrote:


Monica Buescu wrote:

Greetings

This new topic is related with

I need to calculate mode for a base map that is composed by
float values.
r.mode base=b...@permanent cover=1107...@permanent output=saida
And I get:
ERROR: reading r.stats output
ERROR: No rules specified

This means that I'm not being able to apply this function just
because my base map is a Float. Any ideas of how to fix this?

How about r.mapcalc base_integer=int(base) ?

The base map should be integer (category ) values, where the mode
is calculated for all cells with the same cat value, so it indeed
should be an integer raster.


Thanks
Monica

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--
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Arava Development Co. +972-52-3665918
http://www.surfaces.co.il


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Re: [GRASS-user] Question about r.in.xyz

[Daniel Victoria]

In your r.in.xyz the input file is named filev2 while in the r.info
command it says input is named saidav2. Is that what you mean by
different?

Daniel

On Tue, Oct 19, 2010 at 6:15 AM, Franz Schiller
 wrote:
> Hi Hamish
>
>> that's simply a function of what's present in your input data.
>> for floating point values it will just be the next highest
>> integer beyond the maximum data value and can be ignored.
>>
> Uhm but it has to do with the "number of categores"? It's used for Histogram
> only?
>
>>
>> see also the output of r.univar and the display histogram tool.
>>
> Ok r.univar is ok (I guess).
>
>>
>> > - and in the r.info v2 I get a command slightly different from
>> > the one I typed:
>> > r.in.xyz input="C:\Test_areas\graphbased\saidav2" \
>> >   output="v...@permanent" method="mean" type="FCELL" fs=" " \
>> >   x=1 y=2 z=3 zscale=1.0 percent=100
>> > Why?
>>
> But it didn't change my dataset right?
> Franz
>
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[GRASS-user] v.dissolve for lines?

[Bryan Keith]

Hello,

I have a vector line file that has lots of two-vertex lines.  Many of
these two-vertex lines share endpoints and really just make parts of one
longer line.  I'd like to dissolve these lines into one line when they
have the same end point.  It looks like v.dissolve only works for areas. 
Is there somewhere else I should be looking?  Thank you.

Bryan

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[GRASS-user] Re: grass-user Digest, Vol 54, Issue 41

[Margherita Di Leo]

Hi List,

I'm writing a Python script in grass 6.5. At the end of the elaboration the
script pops up the maps on the video using d.mon and d.rast. It opens
several monitors to do that and the maps are displayed one over each other.
Is there a way to display the monitors in a certain position of the screen,
for example one next each other beginning from the upper left of the screen?

Thanks for any help

-Margherita
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Re: [GRASS-user] v.dissolve for lines?

[Micha Silver]

On 10/19/2010 11:17 PM, Bryan Keith wrote:

Hello,

I have a vector line file that has lots of two-vertex lines.  Many of
these two-vertex lines share endpoints and really just make parts of one
longer line.  I'd like to dissolve these lines into one line when they
have the same end point.  It looks like v.dissolve only works for areas.
Is there somewhere else I should be looking?  Thank you.

   

Did you have a look at v.build.polylines ?
Additional note: line vectors have a direction. Two line segments with 
an equivalent node (end point) will *not* connect if they are in 
opposite directions. In this case you can try the v.edit tool=flip 
option (on those segments only)



Bryan

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--
Micha Silver
Arava Development Co. +972-52-3665918
http://www.surfaces.co.il


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Re: [GRASS-user] Re: grass-user Digest, Vol 54, Issue 41

[Glynn Clements]

Margherita Di Leo wrote:

> I'm writing a Python script in grass 6.5. At the end of the elaboration the
> script pops up the maps on the video using d.mon and d.rast. It opens
> several monitors to do that and the maps are displayed one over each other.
> Is there a way to display the monitors in a certain position of the screen,
> for example one next each other beginning from the upper left of the screen?

XDRIVER doesn't provide any mechanism to specify the window position,
but the window manager might provide this functionality (if so, the
details depend upon the window manager in use).

Alternatively, you could use the PNG driver to render the maps as
images, then display the images using a viewer which allows the window
placement to be specified.

Or you could create a single, large monitor window and use d.frame to
position the individual maps within the window.

-- 
Glynn Clements 
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Re: [GRASS-user] v.dissolve for lines?

[Markus Metz]

Micha Silver wrote:
> Bryan Keith wrote:
>>
>> Hello,
>>
>> I have a vector line file that has lots of two-vertex lines.  Many of
>> these two-vertex lines share endpoints and really just make parts of one
>> longer line.  I'd like to dissolve these lines into one line when they
>> have the same end point.  It looks like v.dissolve only works for areas.
>> Is there somewhere else I should be looking?  Thank you.
>>
>>
>
> Did you have a look at v.build.polylines ?
> Additional note: line vectors have a direction. Two line segments with an
> equivalent node (end point) will *not* connect if they are in opposite
> directions.

Each line has two nodes, one at the start and one at the end. If at
the end of one line any other line is starting or ending, this other
line is added to the first line, reversing the direction if necessary.
IOW, two lines with a common node will indeed connect, and the
direction of one line may need to be reversed (done automatically).
Very simple to test by digitizing a simple test vector.

In this case you can try the v.edit tool=flip option (on those
> segments only)

Should not be needed as pre-processing step for v.build.polylines.


Markus M
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