Re: [GRASS-user] Perpendicular projection of points onto line
On 14/05/12 00:54, Marcello Benigno wrote: Hi Professor Carlos, Please take a look here: http://profmarcello.blogspot.com.br/2012/02/grass-snapping-points-to-lines.html Nice solution. You could probably simplify a bit more by using v.in.db instead of v.out.ascii/v.in.ascii. Moritz ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
Hi Professor Carlos, Please take a look here: http://profmarcello.blogspot.com.br/2012/02/grass-snapping-points-to-lines.html Regards, -- *Marcello Benigno B. de Barros Filho* Prof. do Curso Superior de Tecnologia em Geoprocessamento - IFPB Mestre em Ciências Geodésicas e Tecnologias da Geoinformação - UFPE Doutorando em Tecnologia Ambiental e Recursos Hídricos - UFPE http://profmarcello.blogspot.com http://about.me/marcello.benigno ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
Maris, many many thanks. Carlos -- Prof. Carlos Henrique Grohmann Institute of Geosciences - Univ. of São Paulo, Brazil - Digital Terrain Analysis | GIS | Remote Sensing - http://carlosgrohmann.com (http://carlosgrohmann.com/) Can’t stop the signal. Sent with Sparrow (http://www.sparrowmailapp.com/?sig) On Friday, 11 May 2012 at 03:55, Maris Nartiss wrote: v.profile is designed to do exactly what You are looking for. http://grass.osgeo.org/wiki/GRASS_AddOns#v.profile Maris. 2012/5/10 Carlos Grohmann carlos.grohm...@gmail.com (mailto:carlos.grohm...@gmail.com): Hi all I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. Tks -- Carlos Grohmann Sent with Sparrow ___ grass-user mailing list grass-user@lists.osgeo.org (mailto:grass-user@lists.osgeo.org) http://lists.osgeo.org/mailman/listinfo/grass-user ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
v.profile is designed to do exactly what You are looking for. http://grass.osgeo.org/wiki/GRASS_AddOns#v.profile Maris. 2012/5/10 Carlos Grohmann carlos.grohm...@gmail.com: Hi all I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. Tks -- Carlos Grohmann Sent with Sparrow ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Perpendicular projection of points onto line
Hi all I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. Tks -- Carlos Grohmann Sent with Sparrow (http://www.sparrowmailapp.com/?sig) ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
On 05/10/2012 06:31 PM, Carlos Grohmann wrote: Hi all I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. One approach is a three step process: 1- Begin with v.distance from your points to the line. The 'output' parameter will be a line vector of the (perpendicular) connectors from the points to the line. 2- Next do v.patch to merge the connectors to the line. 3- And finally v.clean with tool=break error=connector_points. The 'error' parameter contains all those points where a new intersection had to be created after patching the connectors to the line vector. (There is a chance that one connector will intersect the line exactly on a node, and then v.clean won't find that point since it's not an 'error'. But that's probably a very rare case.) HTH, Micha Tks -- Carlos Grohmann Sent with Sparrow This mail was received via Mail-SeCure System. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user This mail was received via Mail-SeCure System. -- Micha Silver GIS Consultant, Arava Development Co. http://www.surfaces.co.il ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
Carlos wrote: I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. have a look at the v.transects addon script. it does something similar. http://grass.osgeo.org/wiki/GRASS_AddOns#v.transects Hamish ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
Thanks Micha. I though of v.distance but I wasn't sure if the connectors would be perpendicular -- Carlos Grohmann Sent with Sparrow (http://www.sparrowmailapp.com/?sig) On Thursday, 10 de May de 2012 at 14:42, Micha Silver wrote: On 05/10/2012 06:31 PM, Carlos Grohmann wrote: Hi all I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. One approach is a three step process: 1- Begin with v.distance from your points to the line. The 'output' parameter will be a line vector of the (perpendicular) connectors from the points to the line. 2- Next do v.patch to merge the connectors to the line. 3- And finally v.clean with tool=break error=connector_points. The 'error' parameter contains all those points where a new intersection had to be created after patching the connectors to the line vector. (There is a chance that one connector will intersect the line exactly on a node, and then v.clean won't find that point since it's not an 'error'. But that's probably a very rare case.) HTH, Micha Tks -- Carlos Grohmann Sent with Sparrow (http://www.sparrowmailapp.com/?sig) This mail was received via Mail-SeCure System. ___ grass-user mailing list grass-user@lists.osgeo.org (mailto:grass-user@lists.osgeo.org) http://lists.osgeo.org/mailman/listinfo/grass-user This mail was received via Mail-SeCure System. -- Micha Silver GIS Consultant, Arava Development Co. http://www.surfaces.co.il ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Perpendicular projection of points onto line
Oops, of course that the shortest distance will be perpendicular. I should do one thing at a time... trying to code while in a field trip in the Amazon is not the best idea... -- Carlos Grohmann Sent with Sparrow (http://www.sparrowmailapp.com/?sig) On Thursday, 10 de May de 2012 at 17:28, Carlos Grohmann wrote: Thanks Micha. I though of v.distance but I wasn't sure if the connectors would be perpendicular -- Carlos Grohmann Sent with Sparrow (http://www.sparrowmailapp.com/?sig) On Thursday, 10 de May de 2012 at 14:42, Micha Silver wrote: On 05/10/2012 06:31 PM, Carlos Grohmann wrote: Hi all I'm thinking if there is a way to project a series of points into a line, but this projection must be in a direction perpendicular to the line. One approach is a three step process: 1- Begin with v.distance from your points to the line. The 'output' parameter will be a line vector of the (perpendicular) connectors from the points to the line. 2- Next do v.patch to merge the connectors to the line. 3- And finally v.clean with tool=break error=connector_points. The 'error' parameter contains all those points where a new intersection had to be created after patching the connectors to the line vector. (There is a chance that one connector will intersect the line exactly on a node, and then v.clean won't find that point since it's not an 'error'. But that's probably a very rare case.) HTH, Micha Tks -- Carlos Grohmann Sent with Sparrow (http://www.sparrowmailapp.com/?sig) This mail was received via Mail-SeCure System. ___ grass-user mailing list grass-user@lists.osgeo.org (mailto:grass-user@lists.osgeo.org) http://lists.osgeo.org/mailman/listinfo/grass-user This mail was received via Mail-SeCure System. -- Micha Silver GIS Consultant, Arava Development Co. http://www.surfaces.co.il ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
