similar to: Plot point text labels over polygon w/o overlap?

In R's maptools package, is there a built-in function to test if a given point is "inside" a given polygon on the map? The map was loaded from an ESRI Shapefile. The point's latitude and longitude are known. Thank you! Aleks -- ------------------------ Aleksandr Andreev Fulbright Fellow Graduate School of Management St Petersburg State University

Hi, I am working with a SpatialPolygonsDataFrame of many islands. There are a lot of polygons (islands) composing my SpatialPolygonsDataFrame. I want to extract the elevation of each island. I need to separate the different polygons (like dissolve function in arcgis), to have the elevation of each island. Do you have any idea how can I do that ? I already read a lot of forum, and read the

R-listers, Given a polygon and a circle defined by its center coordinates and a radius, I would like to calculate the area of overlap. I know that I can create a polygon from the circle and then use available packages to get the area of the intersection. However, because the polygon is of a fixed size and I will be doing this for circles of varying sizes, I'm concerned about

In Germany the Unemployment Agency uses a sectioning of the german map that is different from the usual Administrative Boundaries. Some demographic data are available in Administrative Boundaries only, some in Unemployment Boundaries only. I would like to generate estimates in one boundary system of data availabe in the other boundary system, and would appreciate advice concerning the following

# polygon ignores requests to have its border transparent, look at par(bg="transparent") plot(c(0, 3), 0:1) polygon(c(0, 1, 1, 0), c(0, 0, 1, 1), border=NA, col = 0) polygon(c(1, 2, 2, 1), c(0, 0, 1, 1), border="transparent", col = 0) polygon(c(2, 3, 3, 2), c(0, 0, 1, 1), border=0, col = 0) # a quick fix for erase.screen() is the following erase.screen <- function (n =

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

Hi there, I'm having trouble working out how to change the colors of polygon shading lines. If I plot a polygon with polygon(poly,density=30,borders=gray(0.5)) I get gray borders but black shading lines; I have tried adding col=gray(0.5), bg=gray(0.5) and fg=gray(0.5), but no luck. How can I change the colors of the shading? The help file doesn't seem to detail this, so any

Hello R-list, I am plotting a weighted linear regression in R. The points on my chart are also scaled to sample size, so some points are large, some are small. I have figured out everything I need using the plot() function: how to plot the points, scale them by sample size, weight the linear regression by sample size, plot that line, and plot the labels for the points. However, although the

Hi: I am practicing with the attached shapefile and was wondering if I can get some help. Haven't used 'rgdal' and 'maptools' much but it appears to be a great way bring map data into R. Please take a look at the comments and let me know if I need to explain better what I am trying to accomplish. library(rgdal) library(maptools) library(ggplot2) dsn="C:/Documents and

Dear list, I have a question regarding the included polygon in the khat function of the splancs library defining the area where points appear. I have not only one simple polygon included, my map includes several islands. I read my map which was a shape file by readShapeSpatial of the maptools library. Then I split up the SpatialPolygonsDataFrame into the included polygons by coor <- NULL

Full_Name: Greg Kochanski Version: 2.2.1 OS: Debian Linux (testing) Submission from: (NULL) (212.159.16.190) This is really a feature request. When you do mosaicplot() on a data set where the probability of several nearby rows is small, then the labels for those rows are plotted overlapping each other. This situation can be improved by calling mosaicplot() with a large value of

Dear R-users, I have created a map with plot location using longitude/latitude coordinates with the PlotOnStaticMap() function of the RgoogleMaps package. Everything works fine until I try to put a polygon on the map. The polygon() function doesn?t work and I need to use the special function PlotPolysOnStaticMap() however this requires a shapefile (which I'm not sure what it is) and not XY

###Dear R users ###I have been using SensoMineR package from CRAN for most of my work in sensory data analysis and from my usage experience, I encountered some areas for improvement and considered ###modifying the function in SensoMineR package for my personal use. I felt that it could be useful to share this to the community for enabling adoption by other users where they might require a

Dear all, When a conventional kriging and then a contour plot is limited with a polygon (as possible with krige.conv and contour.kriging), the polygon border is displayed in black by default. > kc<-krige.conv(CZdata,loc=pred.grid,borders=czpoly,krige=krige.control(obj.m=ls)) > plot(CZcoord,xlab="x",ylab="y",type="n",asp=1) >

Dear all, I would like to produce a map with information about the patenting activity in German districts, by coloring districts with different degrees of patenting activity in different colors. I work with the packages maptools, maps and spdep. The map data is read from an external .shp file (+ the corresponding .shx and .dbf files). Plotting a map with the IDs or the patenting indicator itself

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"

Hi, I have a problem that concerns combination of the package Maptools and Splancs I have 2 shapefiles that i want to manipulate (one of type point and one polygon).I import them in R using Maptools but then i can't estimate a quartic Kernel using Splancs. The package doesn't recognize the shapes (invalid points and poly argument).I don't know if this is an easy task but i have

I am not entirely sure what is going on. I am sure that I am missing something. maptools won't detach... Thanks for all of your help. R 2.11.1 OS Ubuntu 10.04 R --vanilla install.packages("sp", dep=TRUE) Loading required package: reshape Loading required package: plyr Loading required package: grid Loading required package: proto This is vegan 1.17-3 Loading required package:

Dear R-helpers, the problem I'm facing today is to convince lattice to paint some areas in gray. The areas I would like to have in gray, are confidence bands I've googled around in the mailing list archives and eventually find some clues. This link is my starting point http://tolstoy.newcastle.edu.au/R/e2/help/07/04/15595.html I'm reproducing here the code for your convenience est

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