[GRASS-dev] error in georeferencing points on import with v.in.ascii

GRASS GIS GRASS GIS developer
,
1

Michael wrote:

Here is the command:
v.in.ascii --overwrite input=/Users/cmbarton/sites_out
/sites_out.csv output=sites_test separator=, skip=1 x=15
y=16 cat=0

Here is the csv file:

(got it)

Once imported, take a look at the sites in the lower left.
You can see the pairs of sites that should be the same
location.

seems that it's ok, v.out.ascii looks good. I think the GUI query
tool is just picking up the nearby cat 15 at -30626,4116558,
versus cat 46 and 47 at -31415|4116150.

see attached screenshot. the two coords you posted are the two
triangles. (d.mark addon)

as for if the wx query tool will show you attribute data for
both overlapping points (like QGIS does), I don't know.

the wx digitizer has a threshold option for snapping, there
doesn't seem to be a similar mouse-proximity adjustment for
the query tool. maybe that doesn't need an adjustment, just a
change from 10px to 5px (even better if it could deal with diff't
screen DPIs)

Hamish

ps- background (etopo1) is a bit crude as r.in.onearth stopped
working again/JPL changed their tiled WMS again?
pps- er, the vector query tool defaults to edit mode?

(attachments)

lagos.png

2

If it was just grabbing the coordinates from the screen, I would not be worried. But when I do a query, it is clearly pulling up the two points with the same x and y, and showing them with different topological coordinates. I suppose that could still be some kind of display artifact. I have to head out with friends now but will try the command to upload topology to see if that gets it right. But even if it does, the display should not be showing these two points in different places, a couple hundred meters apart.

Michael
____________________
C. Michael Barton
Director, Center for Social Dynamics & Complexity
Professor of Anthropology, School of Human Evolution & Social Change
Arizona State University

voice: 480-965-6262 (SHESC), 480-727-9746 (CSDC)
fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC)
www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu

On Jun 8, 2013, at 5:50 PM, Hamish <hamish_b@yahoo.com>
wrote:

Michael wrote:

Here is the command:
v.in.ascii --overwrite input=/Users/cmbarton/sites_out
/sites_out.csv output=sites_test separator=, skip=1 x=15
y=16 cat=0

Here is the csv file:

(got it)

Once imported, take a look at the sites in the lower left.
You can see the pairs of sites that should be the same
location.

seems that it's ok, v.out.ascii looks good. I think the GUI query
tool is just picking up the nearby cat 15 at -30626,4116558,
versus cat 46 and 47 at -31415|4116150.

see attached screenshot. the two coords you posted are the two
triangles. (d.mark addon)

as for if the wx query tool will show you attribute data for
both overlapping points (like QGIS does), I don't know.

the wx digitizer has a threshold option for snapping, there
doesn't seem to be a similar mouse-proximity adjustment for
the query tool. maybe that doesn't need an adjustment, just a
change from 10px to 5px (even better if it could deal with diff't
screen DPIs)

Hamish

ps- background (etopo1) is a bit crude as r.in.onearth stopped
working again/JPL changed their tiled WMS again?
pps- er, the vector query tool defaults to edit mode?<lagos.png>

3

On Sun, Jun 9, 2013 at 2:50 AM, Hamish <hamish_b@yahoo.com> wrote:

Michael wrote:

Here is the command:
v.in.ascii --overwrite input=/Users/cmbarton/sites_out
/sites_out.csv output=sites_test separator=, skip=1 x=15
y=16 cat=0

Here is the csv file:

(got it)

Once imported, take a look at the sites in the lower left.
You can see the pairs of sites that should be the same
location.

seems that it's ok, v.out.ascii looks good. I think the GUI query
tool is just picking up the nearby cat 15 at -30626,4116558,
versus cat 46 and 47 at -31415|4116150.

Works for me too, cats 46 and 47 are exactly in top of each other. The
grid in the attached screenshot is a 1 cm grid.

Markus M

see attached screenshot. the two coords you posted are the two
triangles. (d.mark addon)

as for if the wx query tool will show you attribute data for
both overlapping points (like QGIS does), I don't know.

the wx digitizer has a threshold option for snapping, there
doesn't seem to be a similar mouse-proximity adjustment for
the query tool. maybe that doesn't need an adjustment, just a
change from 10px to 5px (even better if it could deal with diff't
screen DPIs)

Hamish

ps- background (etopo1) is a bit crude as r.in.onearth stopped
working again/JPL changed their tiled WMS again?
pps- er, the vector query tool defaults to edit mode?
_______________________________________________
grass-dev mailing list
grass-dev@lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/grass-dev

(attachments)

points_grid.png

4

Thanks for the reassurance. I just did v.to.db and it uploads the correct (and same) coordinates to every pair of points in the same locale. So the problem is with the display and interactive query.

This can be very misleading for someone looking at the data. Not sure what is causing this.

Michael
____________________
C. Michael Barton
Director, Center for Social Dynamics & Complexity
Professor of Anthropology, School of Human Evolution & Social Change
Arizona State University

voice: 480-965-6262 (SHESC), 480-727-9746 (CSDC)
fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC)
www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu

On Jun 9, 2013, at 1:18 AM, Markus Metz <markus.metz.giswork@gmail.com>
wrote:

On Sun, Jun 9, 2013 at 2:50 AM, Hamish <hamish_b@yahoo.com> wrote:

Michael wrote:

Here is the command:
v.in.ascii --overwrite input=/Users/cmbarton/sites_out
/sites_out.csv output=sites_test separator=, skip=1 x=15
y=16 cat=0

Here is the csv file:

(got it)

Once imported, take a look at the sites in the lower left.
You can see the pairs of sites that should be the same
location.

seems that it's ok, v.out.ascii looks good. I think the GUI query
tool is just picking up the nearby cat 15 at -30626,4116558,
versus cat 46 and 47 at -31415|4116150.

Works for me too, cats 46 and 47 are exactly in top of each other. The
grid in the attached screenshot is a 1 cm grid.

Markus M

see attached screenshot. the two coords you posted are the two
triangles. (d.mark addon)

as for if the wx query tool will show you attribute data for
both overlapping points (like QGIS does), I don't know.

the wx digitizer has a threshold option for snapping, there
doesn't seem to be a similar mouse-proximity adjustment for
the query tool. maybe that doesn't need an adjustment, just a
change from 10px to 5px (even better if it could deal with diff't
screen DPIs)

Hamish

ps- background (etopo1) is a bit crude as r.in.onearth stopped
working again/JPL changed their tiled WMS again?
pps- er, the vector query tool defaults to edit mode?
_______________________________________________
grass-dev mailing list
grass-dev@lists.osgeo.org
grass-dev Info Page

<points_grid.png>