I try to measure plants (mosses, mainly Pleurozium schreberi) using GIS
software. I have scanned images of mosses and I want measure main lenght
and lenght of all branches with their position. I think this is similar
problem as with measure river lenght with lenghts and position of all
tributaries.
I'm new in GRASS and I've got lost in all commands. If anyone has idea how
to solve above problem I'll feel very grateful for any information.
Slawomir K. Duda
Dept. of Ecology and Nature Prot.
Wroclaw Univ.
I try to measure plants (mosses, mainly Pleurozium schreberi) using GIS
software. I have scanned images of mosses and I want measure main lenght
and lenght of all branches with their position. I think this is similar
problem as with measure river lenght with lenghts and position of all
tributaries.
I'm new in GRASS and I've got lost in all commands. If anyone has idea how
to solve above problem I'll feel very grateful for any information.
Slawomir,
What you need is network analysis, and I do not know if GRASS has this
capability. GRASS does most of its analyses using raster data, not vector
data. Just this past weekend I thought of a number of applications where
vector-based network analyses would be helpful to me. I was going to
investigate whether or not GRASS has this capability now.
Perhaps someone more knowledgeable will answer and we will both know.
Rich
Dr. Richard B. Shepard, President
Applied Ecosystem Services, Inc. (TM)
Making environmentally-responsible mining happen. (SM)
--------------------------------
2404 SW 22nd Street | Troutdale, OR 97060-1247 | U.S.A.
+ 1 503-667-4517 (voice) | + 1 503-667-8863 (fax) | rshepard@appl-ecosys.com
On Mon, Feb 26, 2001 at 06:45:57AM -0800, Rich Shepard wrote:
On Mon, 26 Feb 2001, Slawomir K. Duda wrote:
> I try to measure plants (mosses, mainly Pleurozium schreberi) using GIS
> software. I have scanned images of mosses and I want measure main lenght
> and lenght of all branches with their position. I think this is similar
> problem as with measure river lenght with lenghts and position of all
> tributaries.
> I'm new in GRASS and I've got lost in all commands. If anyone has idea how
> to solve above problem I'll feel very grateful for any information.
Slawomir,
What you need is network analysis, and I do not know if GRASS has this
capability. GRASS does most of its analyses using raster data, not vector
data. Just this past weekend I thought of a number of applications where
vector-based network analyses would be helpful to me. I was going to
investigate whether or not GRASS has this capability now.
Perhaps someone more knowledgeable will answer and we will both know.
To Roberto Micarelli:
As you are working on GRASS vector network analysis, do you
have any news for us? Probably you need assistance to implement
your working tool into GRASS (I remember such a mail). Please
let us know about the status,
As you are working on GRASS vector network analysis, do you
have any news for us? Probably you need assistance to implement
your working tool into GRASS (I remember such a mail). Please
let us know about the status,
Thank you, Markus, for the information.
Just this weekend I learned the term for the GIS programming insight I've
wanted to learn for years, and I've started on the path. From what I've read
so far, these techniques are based on graph theory and making minimal
spanning trees. But, they'd apply just as well to river systems and roads.
If you get an answer, please pass it on. I don't want to re-invent the
wheel, but this is on my wish list, too.
Rich
Dr. Richard B. Shepard, President
Applied Ecosystem Services, Inc. (TM)
Making environmentally-responsible mining happen. (SM)
--------------------------------
2404 SW 22nd Street | Troutdale, OR 97060-1247 | U.S.A.
+ 1 503-667-4517 (voice) | + 1 503-667-8863 (fax) | rshepard@appl-ecosys.com