Displaying 20 results from an estimated 10000 matches similar to: "Indentify polygons that are on the border of a shapefile"
2011 Feb 18
1
How to calculate the perimeter and common border of polygons?
Dear R-users,
Is there any way of calculating the perimeter of a polygon in a shapefile
object? Furthermore, how to calculate the length of the common border of two
polygons?
I've searched the code of spded, but could not find a hint on how to do it.
Thank you very much,
Leo.
[[alternative HTML version deleted]]
2024 May 17
0
[External] Re: Removing polygons from shapefile of Scotland and Islands
Scotland is the second feature in the UK data, so get it and split this one
MULTIPOLYGON feature into individual POLYGONS
scot = st_cast(the_uk$geometry[2],"POLYGON")
# which is the largest polygon?
which.max(st_area(scot))
[1] 1
# the first one. ok...
plot(scot[[1]]) # mainland
# add the rest of the islands for context, in grey, maybe to show they're
outside our study area:
2010 Dec 16
0
Convert tileplot's trellis to shapefile/ Add values to voronoi polygon
I would like to create a voronoi map that can show me point values like the
ones in colum street_cle. I was able to do it in tileplot(latticeExtra) like the
ones attached, and with the following commands:
xy=list(x=x2$X, y=x2$Y)
xy$street_cle <- x2$street_cle
tileplot(street_cle~ x*y, xy)
But this is a trellis. Is it possible to be converted to a shapefile or image so
I can plot it using
2004 Feb 25
2
writing polygons/segments to shapefiles (.shp) or other ArCGIS compatible file
I am not sure a previous e-mail reached the list (no mail aknowledgement from R-boundle etc.). The question was how to write polygon
or segment coordinates into a shapefile set or any other ArcGIS supported format. The library shapefiles seems to do something but
the documentation is a bit beyond of my mind.... and I cannot get the meaning of the functions write**** and its application to the
case
2017 Jun 01
0
[spatstat] Convert shapefile to pixel image
Dear all,
I am currently working with the spatstat package, using windows and pixel images.
First:
My aim is to transform a shapefile (see attached) into a pixel image.
My idea is to start transforming the shapefile into a Spatial Polygon file:
x <- readShapeSpatial("200001441.shp")
y <- as(x, "SpatialPolygons")
z <- as.owin(y)
Given z, I want to identify each
2017 Jun 01
0
[spatstat] Convert shapefile to pixel image
On 02/06/17 01:17, Lluis.Hurtado at uv.es wrote:
> Dear all,
>
> I am currently working with the spatstat package, using windows and pixel images.
>
> First:
>
> My aim is to transform a shapefile (see attached) into a pixel image.
>
> My idea is to start transforming the shapefile into a Spatial Polygon file:
>
> x <-
2004 Feb 26
1
writing polygons/segments to shapefiles (.shp) or other A rcGIS compatible file
The main limitation of the shapefiles package that I put together is that it
does not create shapefiles from R objects - rather it only writes shapefiles
that have been read into R and manipulated within the constraints of the
existing file structure. By this I mean that for example you can change the
coordinates of points and write them back out. Or you can add a bunch of
blank columns in the
2017 Jun 01
3
[spatstat] Convert shapefile to pixel image
Dear all,
I am currently working with the spatstat package, using windows and pixel images.
First:
My aim is to transform a shapefile (see attached) into a pixel image.
My idea is to start transforming the shapefile into a Spatial Polygon file:
x <- readShapeSpatial("200001441.shp")
y <- as(x, "SpatialPolygons")
z <- as.owin(y)
Given z, I want to identify each
2003 Dec 01
1
Re: using shapefile as owin
My sincerest apologies, as this is a very elementary problem, but I have
searched through archives and FAQs and on the web, and I am at the end of my
own resources.
I need to do analysis of a spatial point process occuring with four
counties, using spatstat. I've had no trouble importing the shapefiles, but
I can't seem to figure out what I need to do in order to use the boundary as
an
2023 Nov 20
1
Calculating volume under polygons
Dear all;
I am trying to calculate volume under each polygon of a shapefile according
to a DEM.
when I run the code, it gives me an error as follows.
"
Error in h(simpleError(msg, call)) :
error in evaluating the argument 'x' in selecting a method for function
'addAttrToGeom': sp supports Z dimension only for POINT and MULTIPOINT.
use `st_zm(...)` to coerce to XY dimensions
2007 Aug 13
0
Reading polygon shapefiles in splancs
Dear List,
I'm trying to import a multiple polygon shapefile in splancs. I've found the following command but it seems to work only for single polygons:
Name_of_splancs_polygon<-getPolygonCoordsSlot (getPolygonsPolygonsSlot(getSpPpolygonsSlot(name_of_sp_polygon) [[1]]) [[1]])
I've tried to change the numbers but it seams to choose polygons instead of importing them
2006 Nov 30
2
*** caught segfault *** error
Dear R users,
I use R 2.4.0 on an iMac running Mac OS X 10.4.8, with a 2.16GHz
Intel Core 2 Duo and 2GB 667 MHz DDR2 SDRAM.
> sessionInfo()
R version 2.4.0 (2006-10-03)
i386-apple-darwin8.8.1
locale:
es_ES.UTF-8/es_ES.UTF-8/es_ES.UTF-8/C/es_ES.UTF-8/es_ES.UTF-8
attached base packages:
[1] "methods" "stats" "graphics" "grDevices"
2013 Feb 14
1
Clip a contour with shapefile while using contourplot
Hi, I have done the interpolation for my data and I was able to create the
contours in multipanel with the help of Pascal. Now, I want to clip the
contour with the shapefile. I want only the portion of contour to be
displayed which falls inside the boundary of the shapefile.
The data mydata.csv can be found on
https://www.dropbox.com/s/khi7nv0160hi68p/mydata.csv
The data for shapefile can be
2009 Aug 14
1
extract data from shapefiles
I'm hoping that someone could guide me in how to extract data from shapefiles. I want to extract data from a shapefile (classed as "SpatialPolygonsDataFrame") and more specifically, the data is contained within the slot called "coords" from the class "polygons" within this file and despite my best efforts (and much reading!), I'm at a lost.
Many thanks,
Kate
2006 Aug 09
0
R: data.frame to shape
assuming that the rows are sorted correctly
dat
id x y
1 50 1647685 4815259
2 50 1647546 4815196
3 50 1647454 4815294
4 50 1647405 4815347
5 50 1647292 4815552
6 50 1647737 4815410
7 74 1647555 4815201
8 74 1647464 4815023
9 74 1646970 4815129
10 74 1646895 4815264
11 74 1646762 4815513
> list.dat<-split(dat, dat$id)
>
> closed.polygons<-lapply(list.dat,
2006 Feb 09
1
Shapefiles
Dear List,
I have examined the sp, maptools, and shapefiles packages (Windows) but
cannot seem to figure out a solution for writing shapefiles for 'curvy
shapes'. The scenario is that I generate a series of polygons, circles, and
ellipses on a plot and would like to convert them to shapefiles. Since the
circles and ellipses are do not return a coordinate list during the plotting
2006 Mar 21
3
transform shapefiles in UTM to lat/long
Dear all:
I have a shapefile in UTM coordinate system and I would like to transform it
to Lat/Log coordinates (WSG84). The package PBSmapping contains function
convUL to transform between the two coordinate systems when data is in the
form of a data frame with attributes specifying the coordinate system.
However, when shapefiles are imported using function read.shape (package
maptools), a list
2001 Feb 16
0
polygon border colors
Simple question: is it true that
polygon (x, y, col=vec, border=vec, ...)
will cycle through the vec colors for fills but not for
the border colors when sending multiple polygons?
thanks,
Denis White
US EPA, 200 SW 35th St, Corvallis, Oregon, 97333 USA
voice: 541.754.4476, email: white.denis at epa.gov
web: www.epa.gov/wed/pages/staff/white/
2005 Sep 06
0
Revised shapefiles package
Now available on CRAN is a revised version of the shapefiles package for
reading and writing shapefiles in R. New additions, courtesy of others,
include the ability to convert a simple R data frame of points,
polylines or polygons to a shp format list, which can then be written
out to a shapefile with write.shp. There is also a function to convert
the read.shp shp format list to a simple data
2002 Aug 26
0
Re: RArcInfo 0.3 (fwd)
Hi,
I have been thinking about your questions and comments. And I think I have
the answers. :D
> the way you draw the polygons has the consequence that if the larger one
> is drawn after the smaller one,
> the color of the smaller one is "overwritten"
> and therefore the map is really wrong in the relevant area.
> so this needs fixing.
Another approach is sorting the