<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000'>Dear all,<br><br>I'm running under an XY location (uprojected).<br>Could be this the problem?<br>We are using a local zero not linked to any reference system.<br>Here the output:<br><br>g.proj -w<br>XY location (unprojected)<br><br> g.region -p<br>projection: 0 (x,y)<br>zone: 0<br>north: 1<br>south: 0<br>west: 0<br>east: 1<br>nsres: 0.0001<br>ewres: 0.0001<br>rows: 10000<br>cols: 10000<br>cells: 100000000<br><br>This is the output of v.clean<br>v.clean input=rill_800_parcellaB_polyline@pierluigi output=rill_800_parcellaB_prune tool=prune threshold=0.1<br>--------------------------------------------------<br>Tool: Threshold<br>Prune: 0.1<br>--------------------------------------------------<br>...<br>--------------------------------------------------<br>Tool: Prune lines/boundaries<br>0 vertices from input 11742 (vertices of given type) removed, i.e. 0.00 %<br>--------------------------------------------------<br><br>Thanks<br><br>Pierluigi<br><br><hr id="zwchr"><div style="color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>Da: </b>"Markus Neteler" <neteler@osgeo.org><br><b>A: </b>"Pierluigi De Rosa" <pierluigi.derosa@gfosservices.it><br><b>Cc: </b>"GRASS user list" <grass-user@lists.osgeo.org><br><b>Inviato: </b>Lunedì, 6 aprile 2015 21:28:14<br><b>Oggetto: </b>Re: [GRASS-user] v.clean error threshold under 2 meters<br><br>Hi Pierluigi,<br><br>On Thu, Apr 2, 2015 at 11:34 AM, Pierluigi De Rosa<br><pierluigi.derosa@gfosservices.it> wrote:<br>> Dear all,<br>><br>> I have a unusual system unit.<br><br>Please tell us which :-)<br><br>> I'm working on a parcel unit for rill<br>> analysis. I'm able to extract the network and I would prune a bit the<br>> resulting output.<br>> All the parcel I'm studying is 10 meters wide and 22 meters long, the mean<br>> average distance between the streams is about 1-2 centimetres. I need to<br>> remove nodes in a threshold of 0.005 meters (half centimetre) but I'm having<br>> problem assigning such threshold to v.clean<br>> I'm running GRASS7.<br>> If I use these thresholds ( 0.005, 0.01,1,) no points are removed.<br>> The first valid working threshold is 2 meters.<br>><br>> Maybe v.clean does not accept value under 1 meter or I'm doing something<br>> wrong?<br><br>v.clean should accept "any" value (and we have used GRASS GIS with<br>microscope data in the nanometer scale).<br><br>Could you post the output of<br><br>g.region -p<br>g.proj -w<br>?<br><br>best<br>Markus<br></div><br></div></body></html>