Re: [GRASS-user] how to change all cats in a vector line
On 30/11/14 06:28, Michael Barton wrote: C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu Thanks César, This is pretty much what I’m doing. However, it is not that simple, it turns out. First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the only way to graph a stream profile for the entire stream. Once I have a set of points with the distance from the beginning or the end of the line stored as an attribute for each point, the rest is easy. It is getting to this step that is hard. If a line is composed of multiple segments—as is the case for any line created with r.stream.extract or r.watershed, and also with r.drain surprisingly—there is nothing that will ignore all of these segments and just give me the distance along the line from one end to the other. This is the case with v.to.points As MarkusN said: you have to use v.build.polylines with cats=first, but then it is easy to get total length with v.to.db or v.to.points if that is what you need (or many other options (get end node coordinates and use v.distance 'to_along' or MarkusM's suggestion: v.net.distance from start to end node along the stream). Here's an example in the NC dataset, using r.stream.order to approximate the main stream: g.region n=227440 s=221640 w=630220 e=637220 res=10 r.watershed --overwrite elevation=elevation@PERMANENT threshold=1 accumulation=accum drainage=direction stream=streams r.stream.order --overwrite stream_rast=streams@user1 direction=direction@user1 elevation=elevation@PERMANENT accumulation=accum@user1 stream_vect=streams horton=horton v.extract --overwrite input=streams@user1 where=horton=3 output=main_stream v.build.polylines --overwrite input=main_stream@user1 output=main_stream_poly cats=first then: v.to.db (result=11312.5) or v.to.points input=main_stream@user1 output=main_stream_points dmax=1 db.select sql=select round(max(along)) from main_stream_points_2 round(max(along)) 11312.5 Moritz ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
v.build.polylines is indeed part of what is needed. But it is not enough to be able to use v.to.points in the data I have—and this is not a weirdly meandering stream, just a Mediterranean barranco. A major part of the problem is in the raster to vector conversion. I’ve been using r.to.vect. But it breaks the resulting line into multiple segments and assigns different cat numbers to the segments. If the segments all connect cleanly, v.build.polylines may combine the segments. But I’ve tried using cat=first and it continues to assign multiple cats to the segments. To get a single line, what I have to do currently is: v.clean v.build.polylines with cats=no v.category with option=del ## may not be necessary but I’ve had enough inconsistent results to want to make sure on this v.category with option=add cat=1 step=0 ## this gets me a vector with cat=1 for all parts. repeat the above a 2nd time This gives a sufficiently clean single-object line with a single cat number that I can run v.to.points on. Maybe r.stream.order does a cleaner job in raster to vector conversion. It’s worth a try. Unfortunately, I can’t use the stream order info to extract a stream since I want the stream from its headwaters (stream order = 1) to its outlet (stream order 1). Ideally, there would be a module where I could enter the coordinates of the upstream end of a stream, it would extract the entire watercourse as a single object to its downstream end, edge of map, or a defined outlet stop point. Then I could run v.to.points and v.what.rast to get profile data. OR in a a stream profile module, it would run these for me. I could do it in Python if I could extract a clean vector (one object, one cat, no loops or self-crossing) of a single stream from a stream network created with r.watershed or r.stream.extract. AFAICT, there is nothing available in GRASS that can do this. Kind of surprising. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Dec 1, 2014, at 9:31 AM, Moritz Lennert mlenn...@club.worldonline.be wrote: On 30/11/14 06:28, Michael Barton wrote: C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu Thanks César, This is pretty much what I’m doing. However, it is not that simple, it turns out. First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the only way to graph a stream profile for the entire stream. Once I have a set of points with the distance from the beginning or the end of the line stored as an attribute for each point, the rest is easy. It is getting to this step that is hard. If a line is composed of multiple segments—as is the case for any line created with r.stream.extract or r.watershed, and also with r.drain surprisingly—there is nothing that will ignore all of these segments and just give me the distance along the line from one end to the other. This is the case with v.to.points As MarkusN said: you have to use v.build.polylines with cats=first, but then it is easy to get total length with v.to.db or v.to.points if that is what you need (or many other options (get end node coordinates and use v.distance 'to_along' or MarkusM's suggestion: v.net.distance from start to end node along the stream). Here's an example in the NC dataset, using r.stream.order to approximate the main stream: g.region n=227440 s=221640 w=630220 e=637220 res=10 r.watershed --overwrite elevation=elevation@PERMANENT threshold=1 accumulation=accum drainage=direction stream=streams r.stream.order --overwrite stream_rast=streams@user1 direction=direction@user1 elevation=elevation@PERMANENT accumulation=accum@user1 stream_vect=streams horton=horton v.extract --overwrite input=streams@user1 where=horton=3 output=main_stream v.build.polylines --overwrite input=main_stream@user1 output=main_stream_poly cats=first then: v.to.db (result=11312.5) or v.to.points input=main_stream@user1 output=main_stream_points dmax=1
Re: [GRASS-user] how to change all cats in a vector line
Hi Michael, I have not read the entire thread, but maybe follwowing might work if you want to extract this upstream-downstream watercourse in raster format: 1) Use r.cost with your outlet as starting point and your cell resolution as cost surface. So the output is a pseudo-elevation map with increasing values in upstream direction 2) use r.drain to extract the main course in downstream direction based on a defined upstream end and the pseudo-elevation map created by r.cost. 3) Than you can use r.to.vect to convert your raster cells to vectors and extract your distance per point (cummulative cost) and your elevation. Maybe this might help in on or the other way. best, Johannes On Mon, Dec 1, 2014 at 7:21 PM, Michael Barton michael.bar...@asu.edu wrote: v.build.polylines is indeed part of what is needed. But it is not enough to be able to use v.to.points in the data I have—and this is not a weirdly meandering stream, just a Mediterranean barranco. A major part of the problem is in the raster to vector conversion. I’ve been using r.to.vect. But it breaks the resulting line into multiple segments and assigns different cat numbers to the segments. If the segments all connect cleanly, v.build.polylines may combine the segments. But I’ve tried using cat=first and it continues to assign multiple cats to the segments. To get a single line, what I have to do currently is: v.clean v.build.polylines with cats=no v.category with option=del ## may not be necessary but I’ve had enough inconsistent results to want to make sure on this v.category with option=add cat=1 step=0 ## this gets me a vector with cat=1 for all parts. repeat the above a 2nd time This gives a sufficiently clean single-object line with a single cat number that I can run v.to.points on. Maybe r.stream.order does a cleaner job in raster to vector conversion. It’s worth a try. Unfortunately, I can’t use the stream order info to extract a stream since I want the stream from its headwaters (stream order = 1) to its outlet (stream order 1). Ideally, there would be a module where I could enter the coordinates of the upstream end of a stream, it would extract the entire watercourse as a single object to its downstream end, edge of map, or a defined outlet stop point. Then I could run v.to.points and v.what.rast to get profile data. OR in a a stream profile module, it would run these for me. I could do it in Python if I could extract a clean vector (one object, one cat, no loops or self-crossing) of a single stream from a stream network created with r.watershed or r.stream.extract. AFAICT, there is nothing available in GRASS that can do this. Kind of surprising. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Dec 1, 2014, at 9:31 AM, Moritz Lennert mlenn...@club.worldonline.be wrote: On 30/11/14 06:28, Michael Barton wrote: C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu Thanks César, This is pretty much what I’m doing. However, it is not that simple, it turns out. First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the only way to graph a stream profile for the entire stream. Once I have a set of points with the distance from the beginning or the end of the line stored as an attribute for each point, the rest is easy. It is getting to this step that is hard. If a line is composed of multiple segments—as is the case for any line created with r.stream.extract or r.watershed, and also with r.drain surprisingly—there is nothing that will ignore all of these segments and just give me the distance along the line from one end to the other. This is the case with v.to.points As MarkusN said: you have to use v.build.polylines with cats=first, but then it is easy to get total length with v.to.db or v.to.points if that is what you need (or many other options (get end node coordinates and use v.distance
Re: [GRASS-user] how to change all cats in a vector line
This is exactly what I’m doing. The problems come when I want to sample the vector stream at regular intervals. r.to.vect splits the resulting vector line into multiple segments with different cats for some reason. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Dec 1, 2014, at 11:51 AM, Johannes Radinger johannesradin...@gmail.commailto:johannesradin...@gmail.com wrote: Hi Michael, I have not read the entire thread, but maybe follwowing might work if you want to extract this upstream-downstream watercourse in raster format: 1) Use r.cost with your outlet as starting point and your cell resolution as cost surface. So the output is a pseudo-elevation map with increasing values in upstream direction 2) use r.drain to extract the main course in downstream direction based on a defined upstream end and the pseudo-elevation map created by r.cost. 3) Than you can use r.to.vect to convert your raster cells to vectors and extract your distance per point (cummulative cost) and your elevation. Maybe this might help in on or the other way. best, Johannes On Mon, Dec 1, 2014 at 7:21 PM, Michael Barton michael.bar...@asu.edumailto:michael.bar...@asu.edu wrote: v.build.polylines is indeed part of what is needed. But it is not enough to be able to use v.to.points in the data I have—and this is not a weirdly meandering stream, just a Mediterranean barranco. A major part of the problem is in the raster to vector conversion. I’ve been using r.to.vect. But it breaks the resulting line into multiple segments and assigns different cat numbers to the segments. If the segments all connect cleanly, v.build.polylines may combine the segments. But I’ve tried using cat=first and it continues to assign multiple cats to the segments. To get a single line, what I have to do currently is: v.clean v.build.polylines with cats=no v.category with option=del ## may not be necessary but I’ve had enough inconsistent results to want to make sure on this v.category with option=add cat=1 step=0 ## this gets me a vector with cat=1 for all parts. repeat the above a 2nd time This gives a sufficiently clean single-object line with a single cat number that I can run v.to.points on. Maybe r.stream.order does a cleaner job in raster to vector conversion. It’s worth a try. Unfortunately, I can’t use the stream order info to extract a stream since I want the stream from its headwaters (stream order = 1) to its outlet (stream order 1). Ideally, there would be a module where I could enter the coordinates of the upstream end of a stream, it would extract the entire watercourse as a single object to its downstream end, edge of map, or a defined outlet stop point. Then I could run v.to.points and v.what.rast to get profile data. OR in a a stream profile module, it would run these for me. I could do it in Python if I could extract a clean vector (one object, one cat, no loops or self-crossing) of a single stream from a stream network created with r.watershed or r.stream.extract. AFAICT, there is nothing available in GRASS that can do this. Kind of surprising. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.eduhttp://csdc.asu.edu/ On Dec 1, 2014, at 9:31 AM, Moritz Lennert mlenn...@club.worldonline.bemailto:mlenn...@club.worldonline.be wrote: On 30/11/14 06:28, Michael Barton wrote: C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.eduhttp://csdc.asu.edu/ Thanks César, This is pretty much what I’m doing. However, it is not that simple, it turns out. First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the
Re: [GRASS-user] how to change all cats in a vector line
Thanks to all who replied to this vexing problem. My postdoc Isaac Ullah found what seems to be a good solution to part of this. v.net.path appears to extract a single object, single cat vector line from a stream network if we can give it a starting and ending point. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Dec 1, 2014, at 11:21 AM, Michael Barton michael.bar...@asu.edu wrote: v.build.polylines is indeed part of what is needed. But it is not enough to be able to use v.to.points in the data I have—and this is not a weirdly meandering stream, just a Mediterranean barranco. A major part of the problem is in the raster to vector conversion. I’ve been using r.to.vect. But it breaks the resulting line into multiple segments and assigns different cat numbers to the segments. If the segments all connect cleanly, v.build.polylines may combine the segments. But I’ve tried using cat=first and it continues to assign multiple cats to the segments. To get a single line, what I have to do currently is: v.clean v.build.polylines with cats=no v.category with option=del ## may not be necessary but I’ve had enough inconsistent results to want to make sure on this v.category with option=add cat=1 step=0 ## this gets me a vector with cat=1 for all parts. repeat the above a 2nd time This gives a sufficiently clean single-object line with a single cat number that I can run v.to.points on. Maybe r.stream.order does a cleaner job in raster to vector conversion. It’s worth a try. Unfortunately, I can’t use the stream order info to extract a stream since I want the stream from its headwaters (stream order = 1) to its outlet (stream order 1). Ideally, there would be a module where I could enter the coordinates of the upstream end of a stream, it would extract the entire watercourse as a single object to its downstream end, edge of map, or a defined outlet stop point. Then I could run v.to.points and v.what.rast to get profile data. OR in a a stream profile module, it would run these for me. I could do it in Python if I could extract a clean vector (one object, one cat, no loops or self-crossing) of a single stream from a stream network created with r.watershed or r.stream.extract. AFAICT, there is nothing available in GRASS that can do this. Kind of surprising. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Dec 1, 2014, at 9:31 AM, Moritz Lennert mlenn...@club.worldonline.be wrote: On 30/11/14 06:28, Michael Barton wrote: C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu Thanks César, This is pretty much what I’m doing. However, it is not that simple, it turns out. First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the only way to graph a stream profile for the entire stream. Once I have a set of points with the distance from the beginning or the end of the line stored as an attribute for each point, the rest is easy. It is getting to this step that is hard. If a line is composed of multiple segments—as is the case for any line created with r.stream.extract or r.watershed, and also with r.drain surprisingly—there is nothing that will ignore all of these segments and just give me the distance along the line from one end to the other. This is the case with v.to.points As MarkusN said: you have to use v.build.polylines with cats=first, but then it is easy to get total length with v.to.db or v.to.points if that is what you need (or many other options (get end node coordinates and use
Re: [GRASS-user] how to change all cats in a vector line
But I’ve tried using cat=first and it continues to assign multiple cats to the segments. tested here on my side. from the manual: cats=no - No category number is assigned to a polyline. Also attributes tables linked to the input vector map are not copied to the output vector map. cats=first - Assign to a polyline category number of the first line. All linked attributes tables are copied to the output vector map. cats=multi - If the lines that make up a polyline have different category numbers then v.build.polylines will set the multiple catetory numbers to a polyline. Also all linked attributes tables are copied to the output vector map. none of this options seems to work, as always all cats are copied to the attribute table. bug in v.build.polylines? - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175849.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
You’re right of course. I was getting it confused with v.profile (I’ve gone through a lot of different modules searching for something that works recently). But v.fixed.segmentpoints appears to only create points for a single cat. For the kinds of lines that represent stream courses and which are generated by r.to.vect on the cells created by v.stream.extract, r.watershed, or even r.drain, this won’t work. It only creates points for part of the stream course. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 30, 2014, at 1:22 AM, grass-user-requ...@lists.osgeo.orgmailto:grass-user-requ...@lists.osgeo.org wrote: From: Helmut Kudrnovsky hel...@web.demailto:hel...@web.de To: grass-user@lists.osgeo.orgmailto:grass-user@lists.osgeo.org Date: November 30, 2014 at 12:01:49 AM MST Subject: Re: [GRASS-user] how to change all cats in a vector line I saw this but apparently it is not available for GRASS 7. it is as I wrote it for grass 7. doesn't g.extension do the job? ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
v.fixed.segmentpoints is just a wrapper script of v.Segment http://grass.osgeo.org/grass71/manuals/v.segment.html v.segment is very flexible. you have to define rules (e.g. lines with different cats). IMHO it's the way to go if the river segments have different cats. in v.fixed.segmentpoints I've implemented that the attribute table contains the distance from source, but that's not implemented in v.segment. - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175693.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Thanks for mentioning v.segment Helmut. If I read the docs correctly, it is necessary to send v.segment a text string or file with one line for each point to be created, indicating which cat in the line object is being referenced. I’m trying to automate this for different streams where there can be a variable number of cats, representing line segments of different lengths. And I’m trying to create somewhere between several hundred to several thousand points. So a wrapper like v.fixed.segmentpoint makes more sense, but would need to work for an entire line object or for a set of cats (rather than a single cat). Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 30, 2014, at 12:21 PM, grass-user-requ...@lists.osgeo.orgmailto:grass-user-requ...@lists.osgeo.org wrote: From: Helmut Kudrnovsky hel...@web.demailto:hel...@web.de To: grass-user@lists.osgeo.orgmailto:grass-user@lists.osgeo.org Date: November 30, 2014 at 12:04:09 PM MST Subject: Re: [GRASS-user] how to change all cats in a vector line v.fixed.segmentpoints is just a wrapper script of v.Segment http://grass.osgeo.org/grass71/manuals/v.segment.html v.segment is very flexible. you have to define rules (e.g. lines with different cats). IMHO it's the way to go if the river segments have different cats. in v.fixed.segmentpoints I've implemented that the attribute table contains the distance from source, but that's not implemented in v.segment. - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175693.html Sent from the Grass - Users mailing list archive at Nabble.comhttp://nabble.com/. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Michael Barton wrote Thanks for mentioning v.segment Helmut. If I read the docs correctly, it is necessary to send v.segment a text string or file with one line for each point to be created, indicating which cat in the line object is being referenced. I’m trying to automate this for different streams where there can be a variable number of cats, representing line segments of different lengths. And I’m trying to create somewhere between several hundred to several thousand points. So a wrapper like v.fixed.segmentpoint makes more sense, but would need to work for an entire line object or for a set of cats (rather than a single cat). Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 30, 2014, at 12:21 PM, grass-user-request@.osgeo lt;mailto: grass-user-request@.osgeo gt; wrote: From: Helmut Kudrnovsky lt; hellik@ lt;mailto: hellik@ gt; To: lt; grass-user@.osgeo lt;mailto: grass-user@.osgeo gt; Date: November 30, 2014 at 12:04:09 PM MST Subject: Re: [GRASS-user] how to change all cats in a vector line v.fixed.segmentpoints is just a wrapper script of v.Segment http://grass.osgeo.org/grass71/manuals/v.segment.html v.segment is very flexible. you have to define rules (e.g. lines with different cats). IMHO it's the way to go if the river segments have different cats. in v.fixed.segmentpoints I've implemented that the attribute table contains the distance from source, but that's not implemented in v.segment. - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175693.html Sent from the Grass - Users mailing list archive at Nabble.comlt;http://nabble.com/gt;. ___ grass-user mailing list grass-user@.osgeo http://lists.osgeo.org/mailman/listinfo/grass-user what about a script with a loop through all line cats by using v.fixed.segmentpoints? in v.fixed.segmentpoints I've implemented that only distance between the points (e.g. every 5 meter) has to be given, the calculation for any length is done automatically. - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175728.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Michael Barton wrote: First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the only way to graph a stream profile for the entire stream. You could use v.net + v.net.path to extract a single line from a given headwaters to a given outlet. r.stream.distance should then use the entire course of the selected stream. With a little loop this can be done for all streams of interest. Markus M Once I have a set of points with the distance from the beginning or the end of the line stored as an attribute for each point, the rest is easy. It is getting to this step that is hard. If a line is composed of multiple segments—as is the case for any line created with r.stream.extract or r.watershed, and also with r.drain surprisingly—there is nothing that will ignore all of these segments and just give me the distance along the line from one end to the other. This is the case with v.to.points and v.fixed.segmentpoints. v.profile might do the job but it is not available for GRASS 7. Michael On Nov 29, 2014, at 10:02 PM, grass-user-requ...@lists.osgeo.org wrote: From: César Augusto Ramírez Franco caesar...@gmail.com To: GRASS User List grass-user@lists.osgeo.org Date: November 29, 2014 at 9:13:43 PM MST Subject: Re: [GRASS-user] how to change all cats in a vector line Hello Michael You could use r.stream.order after r.stream.extract to get your stream network ordered, and then, after running r.thin on the ordered stream network, convert it to vector using r.to.vect with the -v flag, that way, each order is a cat, you can them use v.to.points or the add-on suggested below to get topologically-correct points along the stream network, you could also use r.stream.distance and upload distance and elevation to each point using v.what.rast I usually run R from within GRASS and use the spgrass6 library to read the vector map and analyze the data there Regards César. El sáb, 29 de noviembre de 2014 06:29 p.m., Helmut Kudrnovsky hel...@web.de escribió: Michael Barton wrote Hi Markus, What I'm trying to do is start with a raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu ___ 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
Re: [GRASS-user] how to change all cats in a vector line
On Sat, Nov 29, 2014 at 6:16 AM, Michael Barton michael.bar...@asu.edu wrote: I have a vector line that is divided into 12 cat values. I’d like all of the line to have a single cat value. I’ve tried v.category to no avail. If I delete all categories and then add new categories, I get 12 cats again. And I can find no other way to get a single cat for the entire line. Hopefully someone can tell what I’m missing here. Please try to use http://grass.osgeo.org/grass70/manuals/v.build.polylines.html Markus ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Hi Markus, What I'm trying to do is start with a raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 10:20 AM, Michael Barton michael.bar...@asu.edu wrote: Thanks. This helped. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 1:23 AM, Markus Neteler nete...@osgeo.org wrote: On Sat, Nov 29, 2014 at 6:16 AM, Michael Barton michael.bar...@asu.edu wrote: I have a vector line that is divided into 12 cat values. I’d like all of the line to have a single cat value. I’ve tried v.category to no avail. If I delete all categories and then add new categories, I get 12 cats again. And I can find no other way to get a single cat for the entire line. Hopefully someone can tell what I’m missing here. Please try to use http://grass.osgeo.org/grass70/manuals/v.build.polylines.html Markus ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Michael Barton wrote Hi Markus, What I'm trying to do is start http://grasswiki.osgeo.org/wiki/AddOns/GRASS7/vector#v.fixed.segmentpointsa raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 10:20 AM, Michael Barton lt; Michael.Barton@ gt; wrote: Thanks. This helped. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 1:23 AM, Markus Neteler lt; neteler@ gt; wrote: On Sat, Nov 29, 2014 at 6:16 AM, Michael Barton lt; Michael.Barton@ gt; wrote: I have a vector line that is divided into 12 cat values. I’d like all of the line to have a single cat value. I’ve tried v.category to no avail. If I delete all categories and then add new categories, I get 12 cats again. And I can find no other way to get a single cat for the entire line. Hopefully someone can tell what I’m missing here. Please try to use http://grass.osgeo.org/grass70/manuals/v.build.polylines.html Markus ___ grass-user mailing list grass-user@.osgeo http://lists.osgeo.org/mailman/listinfo/grass-user for points along a vector with a fixed distance between the points, see the addon http://grasswiki.osgeo.org/wiki/AddOns/GRASS7/vector#v.fixed.segmentpoints - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175633.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Michael Barton wrote Hi Markus, What I'm trying to do is start with a raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 10:20 AM, Michael Barton lt; Michael.Barton@ gt; wrote: Thanks. This helped. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 1:23 AM, Markus Neteler lt; neteler@ gt; wrote: On Sat, Nov 29, 2014 at 6:16 AM, Michael Barton lt; Michael.Barton@ gt; wrote: I have a vector line that is divided into 12 cat values. I’d like all of the line to have a single cat value. I’ve tried v.category to no avail. If I delete all categories and then add new categories, I get 12 cats again. And I can find no other way to get a single cat for the entire line. Hopefully someone can tell what I’m missing here. Please try to use http://grass.osgeo.org/grass70/manuals/v.build.polylines.html Markus ___ grass-user mailing list grass-user@.osgeo http://lists.osgeo.org/mailman/listinfo/grass-user http://grass.osgeo.org/grass71/manuals/r.stream.extract.html ? - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175634.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
Hello Michael You could use r.stream.order after r.stream.extract to get your stream network ordered, and then, after running r.thin on the ordered stream network, convert it to vector using r.to.vect with the -v flag, that way, each order is a cat, you can them use v.to.points or the add-on suggested below to get topologically-correct points along the stream network, you could also use r.stream.distance and upload distance and elevation to each point using v.what.rast I usually run R from within GRASS and use the spgrass6 library to read the vector map and analyze the data there Regards César. El sáb, 29 de noviembre de 2014 06:29 p.m., Helmut Kudrnovsky hel...@web.de escribió: Michael Barton wrote Hi Markus, What I'm trying to do is start with a raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 10:20 AM, Michael Barton lt; Michael.Barton@ gt; wrote: Thanks. This helped. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 1:23 AM, Markus Neteler lt; neteler@ gt; wrote: On Sat, Nov 29, 2014 at 6:16 AM, Michael Barton lt; Michael.Barton@ gt; wrote: I have a vector line that is divided into 12 cat values. I’d like all of the line to have a single cat value. I’ve tried v.category to no avail. If I delete all categories and then add new categories, I get 12 cats again. And I can find no other way to get a single cat for the entire line. Hopefully someone can tell what I’m missing here. Please try to use http://grass.osgeo.org/grass70/manuals/v.build.polylines.html Markus ___ grass-user mailing list grass-user@.osgeo http://lists.osgeo.org/mailman/listinfo/grass-user http://grass.osgeo.org/grass71/manuals/r.stream.extract.html ? - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6. nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175634.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ 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
Re: [GRASS-user] how to change all cats in a vector line
I saw this but apparently it is not available for GRASS 7. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 4:40 PM, grass-user-requ...@lists.osgeo.orgmailto:grass-user-requ...@lists.osgeo.org wrote: for points along a vector with a fixed distance between the points, see the addon http://grasswiki.osgeo.org/wiki/AddOns/GRASS7/vector#v.fixed.segmentpoints - best regards Helmut ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu Thanks César, This is pretty much what I’m doing. However, it is not that simple, it turns out. First, for a stream profile, you want to isolate a single watercourse. r.stream.extract creates a stream network. Getting stream order does not help with profiling, however. I looked at r.stream.distance. But this calculates distance from each stream junction. I want it for the entire course of the selected stream—from headwaters to outlet. That is the only way to graph a stream profile for the entire stream. Once I have a set of points with the distance from the beginning or the end of the line stored as an attribute for each point, the rest is easy. It is getting to this step that is hard. If a line is composed of multiple segments—as is the case for any line created with r.stream.extract or r.watershed, and also with r.drain surprisingly—there is nothing that will ignore all of these segments and just give me the distance along the line from one end to the other. This is the case with v.to.points and v.fixed.segmentpoints. v.profile might do the job but it is not available for GRASS 7. Michael On Nov 29, 2014, at 10:02 PM, grass-user-requ...@lists.osgeo.orgmailto:grass-user-requ...@lists.osgeo.org wrote: From: César Augusto Ramírez Franco caesar...@gmail.commailto:caesar...@gmail.com To: GRASS User List grass-user@lists.osgeo.orgmailto:grass-user@lists.osgeo.org Date: November 29, 2014 at 9:13:43 PM MST Subject: Re: [GRASS-user] how to change all cats in a vector line Hello Michael You could use r.stream.order after r.stream.extract to get your stream network ordered, and then, after running r.thin on the ordered stream network, convert it to vector using r.to.vect with the -v flag, that way, each order is a cat, you can them use v.to.points or the add-on suggested below to get topologically-correct points along the stream network, you could also use r.stream.distance and upload distance and elevation to each point using v.what.rast I usually run R from within GRASS and use the spgrass6 library to read the vector map and analyze the data there Regards César. El sáb, 29 de noviembre de 2014 06:29 p.m., Helmut Kudrnovsky hel...@web.demailto:hel...@web.de escribió: Michael Barton wrote Hi Markus, What I'm trying to do is start with a raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.eduhttp://csdc.asu.edu/ ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] how to change all cats in a vector line
I tried to install v.profile under GRASS 6.4.4 to see if it would work but it failed to compile. Michael Here are the errors C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 10:29 AM, Michael Barton michael.bar...@asu.edu wrote: Hi Markus, What I'm trying to do is start with a raster stream map from r.drain and convert it to a sequence of vector points, where each point has information as to its position along the stream. I then use the points for sampling a stream profile and related information. Oddly enough, with all of the very useful stream analysis modules, there is nothing I could find to generate the data for a stream profile (distance from outlet or from headwaters vs. elevation). v.to.points does a nice job of creating a sequence of evenly spaced points with information about their location along a line (the along field). BUT, if the line is composed of multiple segments or even if it has an irregularity in it, the along values start over again from 0. The only way I can use it is if I have a very clean and continuous vector line with only a single cat. This has proven surprisingly difficult to obtain reliably from my raster stream map. So far, the only way has been to do a two sequences of v.clean (with thresholds 1.5 X the raster resolution) and v.build.polylines. If you have any better suggestion, I'd love to hear it. Thanks again for the polylines idea. That was a big help. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 10:20 AM, Michael Barton michael.bar...@asu.edu wrote: Thanks. This helped. Michael C. Michael Barton Director, Center for Social Dynamics Complexity Professor of Anthropology, School of Human Evolution Social Change Head, Graduate Faculty in Complex Adaptive Systems Science Arizona State University voice: 480-965-6262 (SHESC), 480-965-8130/727-9746 (CSDC) fax: 480-965-7671 (SHESC), 480-727-0709 (CSDC) www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu On Nov 29, 2014, at 1:23 AM, Markus Neteler nete...@osgeo.org wrote: On Sat, Nov 29, 2014 at 6:16 AM, Michael Barton michael.bar...@asu.edu wrote: I have a vector line that is divided into 12 cat values. I’d like all of the line to have a single cat value. I’ve tried v.category to no avail. If I delete all categories and then add new categories, I get 12 cats again. And I can find no other way to get a single cat for the entire line. Hopefully someone can tell what I’m missing here. Please try to use http://grass.osgeo.org/grass70/manuals/v.build.polylines.html Markus GRASS 6.4.5svn (Penaguila):~ g.extension extension=v.profile operation=add Fetching v.profile from GRASS-Addons SVN (be patient)... Av.profile/main.c Av.profile/v.profile.html Av.profile/Makefile Av.profile/README U v.profile Checked out revision 63296. Compiling v.profile... /Applications/GRASS/GRASS-6.4.app/Contents/MacOS/include/Make/Grass.make:423: warning: overriding commands for target `/Users/cmbarton/Dropbox/GRASS_dropbox/grassdata_dropbox/Penaguila/analysis/.tmp/Michaels-MacBook-Air-3.local/20552.0/dist.x86_64-apple-darwin14/bin' /Applications/GRASS/GRASS-6.4.app/Contents/MacOS/include/Make/Grass.make:414: warning: ignoring old commands for target `/Users/cmbarton/Dropbox/GRASS_dropbox/grassdata_dropbox/Penaguila/analysis/.tmp/Michaels-MacBook-Air-3.local/20552.0/dist.x86_64-apple-darwin14/bin' mkdir -p /Users/cmbarton/Dropbox/GRASS_dropbox/grassdata_dropbox/Penaguila/analysis/.tmp/Michaels-MacBook-Air-3.local/20552.0/dist.x86_64-apple-darwin14/bin mkdir -p /Users/cmbarton/Dropbox/GRASS_dropbox/grassdata_dropbox/Penaguila/analysis/.tmp/Michaels-MacBook-Air-3.local/20552.0/dist.x86_64-apple-darwin14/include/grass mkdir -p /Users/cmbarton/Dropbox/GRASS_dropbox/grassdata_dropbox/Penaguila/analysis/.tmp/Michaels-MacBook-Air-3.local/20552.0/dist.x86_64-apple-darwin14/etc mkdir -p /Users/cmbarton/Dropbox/GRASS_dropbox/grassdata_dropbox/Penaguila/analysis/.tmp/Michaels-MacBook-Air-3.local/20552.0/dist.x86_64-apple-darwin14/driver mkdir -p
Re: [GRASS-user] how to change all cats in a vector line
I saw this but apparently it is not available for GRASS 7. it is as I wrote it for grass 7. doesn't g.extension do the job? - best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/how-to-change-all-cats-in-a-vector-line-tp5175575p5175648.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
