Re: [R-sig-Geo] help: krigged map do not show colours
Anand, I could not open your .grd file in R, I think the .gri file is missing. However, looking at it in a text editor, and comparing with your R-script, it seems something went wrong with your projections. Your .csv-file has LatLong coordinates, but you are setting the projection to +proj=utm +zone=40 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0, the same as you seem to have in your prediction raster. But you need to reproject your observations in this case. # First set the right projection: proj4string(carbon_seq) - CRS(+init=epsg4326) # epsg-code for latlong # Then transform carbon_seq = spTransform(carbon_seq, CRS(+proj=utm +zone=40 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0)) If you do this, your prediction grid should overlap your observations, and the colors should reflect your color ramp. What you essentially did before was to make a prediction thousands of km away from your observations, and then all values will be the same. Best wishes, Jon On 8/4/2015 12:48 PM, Anand Sookun wrote: Dear Jon and Roman Thanks for the reply. Im attaching the code. You may be right that the variogram may be problematic but it fitted well visually. I think also that the prediction grid was not well created. I wiould be grateful to have to hints.code how to create a useful grid and also for the spplot or other alternatives I can send more info if required. Cheers Anand On Tue, Aug 4, 2015 at 1:39 PM, Jon Skoien jon.sko...@jrc.ec.europa.eu mailto:jon.sko...@jrc.ec.europa.eu wrote: Hi, You have attached some data, but we still dont know exactly what you do with the data (do you use the logarithm, how many bins, did you project the data set...?). However, having had a quick look using the LatLong coordinates (not really recommended), I can see that the variogram from this data set is not particularly well defined, and it could well be that you fitted a model with pure nugget effect. In that case you will get the same prediction everywhere and no color differences. Have a look at summary(map) and particularly the summary of var1.pred. You could also plot the variogram of the data together with your model, vmf, and see how they fit. I am not sure what you mean by not being able to create a prediction grid with data included. Do you mean that you want a grid which exactly overlays some of the data points? Matching one point should not be difficult, 2 and 3 should be possible, but you might get some problems with precision (FAQ 7.31). Best wishes, Jon On 8/3/2015 5:30 PM, Anand Sookun wrote: Hi Thank you Roman for your kind response. The data is as attached which is part of the whole dataset. My other problem is that im not able to create an appropriate prediction grid with some data included. The codes which failed to show colour ramps are map - krige(logcarbseq ~ 1, locations = carbon_seq, newdata = map,model = vmf) str(map) print(spplot(map, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, carbon)) print(spplot(map, var1.var,col.regions=cm.colors(64),asp=1, main=OK prediction variance, carbon)) I look forward to hopefully get some solutions. Thanks again and warm regards Anand On Mon, Aug 3, 2015 at 4:09 PM, Roman Luštrik roman.lust...@gmail.com mailto:roman.lust...@gmail.com wrote: What is the variability of the plotted variable? Cheers, Roman On Sun, Aug 2, 2015 at 11:03 AM, Anand Sookun mailto:asoo...@gmail.comasoo...@gmail.com mailto:asoo...@gmail.com wrote: Hi I have kriged my data but the map shows uniform colours - no gradual contour colour plot on map code: print(spplot(k40, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, log-ppm Zn)) thnaks for any help Anand Sookun -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org mailto:R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo -- In God we trust, all others bring data. -- --- /*Anand Sookun (*//*MPhil. *//*PhD Candidate,
Re: [R-sig-Geo] help: krigged map do not show colours
Hi, You have attached some data, but we still dont know exactly what you do with the data (do you use the logarithm, how many bins, did you project the data set...?). However, having had a quick look using the LatLong coordinates (not really recommended), I can see that the variogram from this data set is not particularly well defined, and it could well be that you fitted a model with pure nugget effect. In that case you will get the same prediction everywhere and no color differences. Have a look at summary(map) and particularly the summary of var1.pred. You could also plot the variogram of the data together with your model, vmf, and see how they fit. I am not sure what you mean by not being able to create a prediction grid with data included. Do you mean that you want a grid which exactly overlays some of the data points? Matching one point should not be difficult, 2 and 3 should be possible, but you might get some problems with precision (FAQ 7.31). Best wishes, Jon On 8/3/2015 5:30 PM, Anand Sookun wrote: Hi Thank you Roman for your kind response. The data is as attached which is part of the whole dataset. My other problem is that im not able to create an appropriate prediction grid with some data included. The codes which failed to show colour ramps are map - krige(logcarbseq ~ 1, locations = carbon_seq, newdata = map,model = vmf) str(map) print(spplot(map, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, carbon)) print(spplot(map, var1.var,col.regions=cm.colors(64),asp=1, main=OK prediction variance, carbon)) I look forward to hopefully get some solutions. Thanks again and warm regards Anand On Mon, Aug 3, 2015 at 4:09 PM, Roman Lu�trik roman.lust...@gmail.com mailto:roman.lust...@gmail.com wrote: What is the variability of the plotted variable? Cheers, Roman On Sun, Aug 2, 2015 at 11:03 AM, Anand Sookun asoo...@gmail.com mailto:asoo...@gmail.com wrote: Hi I have kriged my data but the map shows uniform colours - no gradual contour colour plot on map code: print(spplot(k40, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, log-ppm Zn)) thnaks for any help Anand Sookun -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org mailto:R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo -- In God we trust, all others bring data. -- --- /*Anand Sookun (*//*MPhil. *//*PhD Candidate, University of Mauritius)*/ /*Director cum Freelance Consultant*/ /*Soft Sustainable Services (Mauritius)*/ /*Research and Consultancy*/ Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo -- Jon Olav Sk�ien Joint Research Centre - European Commission Institute for Environment and Sustainability (IES) Climate Risk Management Unit Via Fermi 2749, TP 100-01, I-21027 Ispra (VA), ITALY jon.sko...@jrc.ec.europa.eu Tel: +39 0332 789205 Disclaimer: Views expressed in this email are those of the individual and do not necessarily represent official views of the European Commission. [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Re: [R-sig-Geo] help: krigged map do not show colours
Dear Jon and Roman Thanks for the reply. Im attaching the code. You may be right that the variogram may be problematic but it fitted well visually. I think also that the prediction grid was not well created. I wiould be grateful to have to hints.code how to create a useful grid and also for the spplot or other alternatives I can send more info if required. Cheers Anand On Tue, Aug 4, 2015 at 1:39 PM, Jon Skoien jon.sko...@jrc.ec.europa.eu wrote: Hi, You have attached some data, but we still dont know exactly what you do with the data (do you use the logarithm, how many bins, did you project the data set...?). However, having had a quick look using the LatLong coordinates (not really recommended), I can see that the variogram from this data set is not particularly well defined, and it could well be that you fitted a model with pure nugget effect. In that case you will get the same prediction everywhere and no color differences. Have a look at summary(map) and particularly the summary of var1.pred. You could also plot the variogram of the data together with your model, vmf, and see how they fit. I am not sure what you mean by not being able to create a prediction grid with data included. Do you mean that you want a grid which exactly overlays some of the data points? Matching one point should not be difficult, 2 and 3 should be possible, but you might get some problems with precision (FAQ 7.31). Best wishes, Jon On 8/3/2015 5:30 PM, Anand Sookun wrote: Hi Thank you Roman for your kind response. The data is as attached which is part of the whole dataset. My other problem is that im not able to create an appropriate prediction grid with some data included. The codes which failed to show colour ramps are map - krige(logcarbseq ~ 1, locations = carbon_seq, newdata = map,model = vmf) str(map) print(spplot(map, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, carbon)) print(spplot(map, var1.var,col.regions=cm.colors(64),asp=1, main=OK prediction variance, carbon)) I look forward to hopefully get some solutions. Thanks again and warm regards Anand On Mon, Aug 3, 2015 at 4:09 PM, Roman Luštrik roman.lust...@gmail.com wrote: What is the variability of the plotted variable? Cheers, Roman On Sun, Aug 2, 2015 at 11:03 AM, Anand Sookun asoo...@gmail.com asoo...@gmail.com wrote: Hi I have kriged my data but the map shows uniform colours - no gradual contour colour plot on map code: print(spplot(k40, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, log-ppm Zn)) thnaks for any help Anand Sookun -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo -- In God we trust, all others bring data. -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic ___ R-sig-Geo mailing listR-sig-Geo@r-project.orghttps://stat.ethz.ch/mailman/listinfo/r-sig-geo -- Jon Olav Skøien Joint Research Centre - European Commission Institute for Environment and Sustainability (IES) Climate Risk Management Unit Via Fermi 2749, TP 100-01, I-21027 Ispra (VA), ITALY jon.sko...@jrc.ec.europa.eu Tel: +39 0332 789205 Disclaimer: Views expressed in this email are those of the individual and do not necessarily represent official views of the European Commission. -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic To sig geoAug2015.R Description: Binary data vca_raster.grd Description: Binary data ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Re: [R-sig-Geo] help: krigged map do not show colours
Unfortunately we don't have access to all the variables you use in `krige` call. Consider making a reproducible example. Cheers, Roman On Mon, Aug 3, 2015 at 5:30 PM, Anand Sookun asoo...@gmail.com wrote: Hi Thank you Roman for your kind response. The data is as attached which is part of the whole dataset. My other problem is that im not able to create an appropriate prediction grid with some data included. The codes which failed to show colour ramps are map - krige(logcarbseq ~ 1, locations = carbon_seq, newdata = map,model = vmf) str(map) print(spplot(map, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, carbon)) print(spplot(map, var1.var,col.regions=cm.colors(64),asp=1, main=OK prediction variance, carbon)) I look forward to hopefully get some solutions. Thanks again and warm regards Anand On Mon, Aug 3, 2015 at 4:09 PM, Roman Luštrik roman.lust...@gmail.com wrote: What is the variability of the plotted variable? Cheers, Roman On Sun, Aug 2, 2015 at 11:03 AM, Anand Sookun asoo...@gmail.com wrote: Hi I have kriged my data but the map shows uniform colours - no gradual contour colour plot on map code: print(spplot(k40, var1.pred, asp=1, col.regions=bpy.colors(64),main=OK prediction, log-ppm Zn)) thnaks for any help Anand Sookun -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo -- In God we trust, all others bring data. -- --- *Anand Sookun (**MPhil. **PhD Candidate, University of Mauritius)* *Director cum Freelance Consultant* *Soft Sustainable Services (Mauritius)* *Research and Consultancy* Website: http://sustain-ability.webs.com/ https://www.linkedin.com/profile/view?id=161468467trk=nav_responsive_tab_profile_pic -- In God we trust, all others bring data. [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[R-sig-Geo] From spatial points to spatial pictures
Hi everybody, I'm maurizio Marchi and I'm working as a post-doc at the Forestry Research Centre of Arezzo (Italy) and I have a question concerning spatial points management. During my research activities I have to collect data about the crown projection on the ground of trees. The aim is to measure the crown area and to draw a sort of picture on GIS software (QGIS in my case) to analyze the area and the perimeter of the crowns compared to the free area of a plot (generally a circular plot) to have an idea of how much photosynthetic radiation is able to reach the soil. My working steps are: 1) During the survey on the field each crown of each tree is initially drawn collecting 8 points that have to be connected to become a spatial polygon: ###---example of table to be processed TREE POINT X Y 11 xy 12 xy 13 xy 14 xy 15 xy 16 xy 17 xy 18 xy 21 xy 22 xy 23 xy 24 xy 25 xy 26 xy 27 xy 28 xy [..] N8 xy 2) the points,sorted by Tree become the vertices of the polygons 3) The polygons have to be processed to obtain a smoothed polygons, circumscribing the polygonal crowns (e.g. http://grasswiki.osgeo.org/wiki/V.generalize_tutorial) I generally do it on QGIS and GRASS but is there something more appropriate on R to do this? for example with rgdal or sp package? Many thanks -- Maurizio Marchi Calenzano (FI) - Italy ID Skype: maurizioxyz Ubuntu 14.04 LTS linux user 552742 [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Re: [R-sig-Geo] help: krigged map do not show colours
Dear Jon I have to thank you so much for solving this issue. I did't notice that there was a projection and grid problem. I hope I would be able to move forward with my analysis with R and perhaps still need your kind and much appreciated help. Cheers Anand On Wed, Aug 5, 2015 at 12:08 PM, Jon Skoien jon.sko...@jrc.ec.europa.eu wrote: Good. For the next function, I think you are trying to use an sp-function (gridded) on a raster object. You can convert between these, but not necessarily use the same functions. Use spgrid = rasterToPoints(YourRaster, spatial = TRUE) gridded(spgrid) = TRUE if you want to convert your raster layer to a spatial object. Best wishes, Jon On 8/5/2015 10:00 AM, Anand Sookun wrote: Dear John Thanks again. this time it worked but the variogram is not plotting well and some other problems croped. Error in (function (classes, fdef, mtable) : unable to find an inherited method for function ‘gridded’ for signature ‘RasterLayer I will try by looking closely at the scripts and be back to you soon Best Wishes Anand On Wed, Aug 5, 2015 at 11:36 AM, Jon Skoien jon.sko...@jrc.ec.europa.eu wrote: Dear Anand On 8/5/2015 9:03 AM, Anand Sookun wrote: Dear John Greetings I really appreciate your help. Itried what you proposed but got stuck with the following: proj4string(carbon_seq) - CRS(+init=epsg 4326) # epsg-code for latlong Error in CRS(+init=epsg 4326) : no colon in init= string Sorry, there is a : missing, should be CRS(+init=epsg:4326) See if it works better! Jon Also I TRIED AGAIN proj4string(carbon_seq) - CRS(+init=epsg4326) # epsg-code for latlong Error in (function (classes, fdef, mtable) : unable to find an inherited method for function ‘proj4string-’ for signature ‘data.frame, CRS I tried with rgdal but got the same eror require(rgdal) Loading required package: rgdal rgdal: version: 0.8-16, (SVN revision 498) Geospatial Data Abstraction Library extensions to R successfully loaded Loaded GDAL runtime: GDAL 1.10.1, released 2013/08/26 Path to GDAL shared files: C:/Users/Anand/Documents/R/win-library/3.0/rgdal/gdal GDAL does not use iconv for recoding strings. Loaded PROJ.4 runtime: Rel. 4.8.0, 6 March 2012, [PJ_VERSION: 480] Path to PROJ.4 shared files: C:/Users/Anand/Documents/R/win-library/3.0/rgdal/proj im attacing the gri file. Thanks for your time. CHEERS ANAND On Tue, Aug 4, 2015 at 4:55 PM, Jon Skoien jon.sko...@jrc.ec.europa.eujon.sko...@jrc.ec.europa.eu wrote: Anand, I could not open your .grd file in R, I think the .gri file is missing. However, looking at it in a text editor, and comparing with your R-script, it seems something went wrong with your projections. Your .csv-file has LatLong coordinates, but you are setting the projection to +proj=utm +zone=40 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0, the same as you seem to have in your prediction raster. But you need to reproject your observations in this case. # First set the right projection: proj4string(carbon_seq) - CRS(+init=epsg4326) # epsg-code for latlong # Then transform carbon_seq = spTransform(carbon_seq, CRS(+proj=utm +zone=40 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0)) If you do this, your prediction grid should overlap your observations, and the colors should reflect your color ramp. What you essentially did before was to make a prediction thousands of km away from your observations, and then all values will be the same. Best wishes, Jon On 8/4/2015 12:48 PM, Anand Sookun wrote: Dear Jon and Roman Thanks for the reply. Im attaching the code. You may be right that the variogram may be problematic but it fitted well visually. I think also that the prediction grid was not well created. I wiould be grateful to have to hints.code how to create a useful grid and also for the spplot or other alternatives I can send more info if required. Cheers Anand On Tue, Aug 4, 2015 at 1:39 PM, Jon Skoien jon.sko...@jrc.ec.europa.eu mailto:jon.sko...@jrc.ec.europa.eu wrote: Hi, You have attached some data, but we still dont know exactly what you do with the data (do you use the logarithm, how many bins, did you project the data set...?). However, having had a quick look using the LatLong coordinates (not really recommended), I can see that the variogram from this data set is not particularly well defined, and it could well be that you fitted a model with pure nugget effect. In that case you will get the same prediction everywhere and no color differences. Have a look at summary(map) and particularly the summary of var1.pred. You could also plot the variogram of the data together with your model, vmf, and see how they fit. I am not sure what you mean by not being able to create a prediction grid with data included. Do you mean that you want a grid which
Re: [R-sig-Geo] From spatial points to spatial pictures
Can you provide a (small) real set of data (with real values for x y)? On Wed, Aug 5, 2015 at 9:56 AM, Maurizio Marchi mauriziomarch...@gmail.com wrote: photosynthetic radiation ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Re: [R-sig-Geo] From spatial points to spatial pictures
Maurizio provided his data set offline. The code + data + sample plots
are in this gist:
https://gist.github.com/hrbrmstr/e29cf9138e480db9e67d
The data is just as he described it, so it's really just a matter of
creating some polygons from the the points spline interpolation:
library(ggplot2)
library(ggthemes)
library(sp)
#' Make smooth polys from points
#'
#' From: http://gis.stackexchange.com/a/24929/29544
#'
#' @param xy n x 2 matrix with n = k
#' @param k # of vertices to expand points to
#' @param ... other args passed to \code{spline()}
spline.poly - function(xy, vertices, k=3, ...) {
# Wrap k vertices around each end.
n - dim(xy)[1]
if (k = 1) {
data - rbind(xy[(n-k+1):n,], xy, xy[1:k, ])
} else {
data - xy
}
# Spline the x and y coordinates.
data.spline - spline(1:(n+2*k), data[,1], n=vertices, ...)
x - data.spline$x
x1 - data.spline$y
x2 - spline(1:(n+2*k), data[,2], n=vertices, ...)$y
# Retain only the middle part.
cbind(x1, x2)[k x x = n+k, ]
}
# read in the data
trees - read.csv(CrownsExample.csv)
# sort data by tree point
trees - trees[with(trees, order(TREE, POINT)),]
# plot just points colored by tree to make sure points look ok
ggplot(trees, aes(x=X, y=Y, color=factor(TREE))) + coord_equal() +
geom_point()
# small function to avoid anonymous fnction in `by` make a polygon
from our points
make_tree_poly - function(tree) {
tree_pts - spline.poly(as.matrix(tree[, c(X, Y)]), 100)
Polygons(list(Polygon(tree_pts)), ID=unique(tree$TREE))
}
# for each tree, make a set of smoothed polygons then make the whole thing
# a SpatialPolygonsDataFrame so more spatial ops can be done on it (or more
# data stored with it)
tree_polys - SpatialPolygonsDataFrame(
SpatialPolygons(unclass(by(trees, trees$TREE, make_tree_poly)),
proj4string=CRS(+proj=utm +zone=32 +ellps=GRS80
+units=m +no_defs )),
data.frame(id=unique(trees$TREE), row.names=unique(trees$TREE)))
# plot the new polygon tree crowns colored by tree
tree_map - fortify(tree_polys)
ggplot() +
geom_map(data=tree_map, map=tree_map,
aes(x=long, y=lat, fill=id, map_id=id, color=id)) +
geom_point(data=trees, aes(x=X, y=Y)) + # original points just
to show it's accurate
coord_equal() +
theme_map()
On Wed, Aug 5, 2015 at 9:56 AM, Maurizio Marchi
mauriziomarch...@gmail.com wrote:
Hi everybody,
I'm maurizio Marchi and I'm working as a post-doc at the Forestry Research
Centre of Arezzo (Italy) and I have a question concerning spatial points
management.
During my research activities I have to collect data about the crown
projection on the ground of trees. The aim is to measure the crown area
and to draw a sort of picture on GIS software (QGIS in my case) to analyze
the area and the perimeter of the crowns compared to the free area of a
plot (generally a circular plot) to have an idea of how much photosynthetic
radiation is able to reach the soil. My working steps are:
1) During the survey on the field each crown of each tree is initially
drawn collecting 8 points that have to be connected to become a spatial
polygon:
###---example of table to be processed
TREE POINT X Y
11 xy
12 xy
13 xy
14 xy
15 xy
16 xy
17 xy
18 xy
21 xy
22 xy
23 xy
24 xy
25 xy
26 xy
27 xy
28 xy
[..]
N8 xy
2) the points,sorted by Tree become the vertices of the polygons
3) The polygons have to be processed to obtain a smoothed polygons,
circumscribing the polygonal crowns (e.g.
http://grasswiki.osgeo.org/wiki/V.generalize_tutorial)
I generally do it on QGIS and GRASS but is there something more appropriate
on R to do this? for example with rgdal or sp package?
Many thanks
--
Maurizio Marchi
Calenzano (FI) - Italy
ID Skype: maurizioxyz
Ubuntu 14.04 LTS
linux user 552742
[[alternative HTML version deleted]]
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