similar to: Midpoint between coordinates

Dear all, 1. How can I compute the intersecting area between 2 polygons ? 2. I have polygons with coordinates in decimal degrees (i.e. 13 deg 30 min = 13.5 decimal degrees). I want to compute their area and get the results in square meters or square kiometers. Can anyone give me a conversion coefficient or a pointer where I can find this information (sorry for this off topic question) ? Thanks

Starting with the head of a 499 element matrix whose column names are now the labels trom a cut() operation, I needed to get to a vector of midpoints to serve as the basis for plotting a calibration curve ( exp(linear predictor) vs. : > dput(head(dimnames(mtcal)[2][[1]])) # was starting point testvec <- c("(-8.616,-3.084]", "(-3.084,-2.876]",

I have a data set for different time intervals. The data has three comment lines before data for each time interval. For each time interval there are 500 data points. I want to change the dataset such that I have the following format: t1 t2 t3 ................ 0.00208 0.00417 0.00625 ................. a1 a2 a3 ...................

# R for Windows will not send your bug report automatically. # Please copy the bug report (after finishing it) to # your favorite email program and send it to # # r-bugs at r-project.org # ###################################################### This report is joint from Richard Heiberger <rmh at temple.edu> and Burt Holland <bholland at temple.edu>. Burt Holland is the coauthor

Hello list: I am using "cut" and "table" to obtain a frequency table from a numeric sample vector.  The idea is to calculate mean and standard deviation on grouped data.  However, I can't extract the midpoints of the class intervals, which seem to be strings treated as factors.  How do i extract the midpoint? Thanks, jose loreto [[alternative HTML version deleted]]

Hi lily, It's not too hard to do it using dataframes. Getting the indexing right is usually that hardest part: # these values are the centers of the black cells lat<-rep(28:38,11) lon<-rep(98:108,each=11) pop<-sample(80:200,121) # just use the data.frame function blackcells<-data.frame(lat=lat,lon=lon,pop=pop) plot(0,type="n",xlim=c(97.5,108.5),ylim=c(27.5,38.5),

Hi Jim, Thanks. It works. I now have more complex problems. If at each blackcell, there are two variables such as pop and mood. For each variable, there are daily records in one year, so 365 records for pop and 365 records for mood. The averaged values for the redcells should be daily records too. What kind of format do you recommend for this problem? Right now, I just get the latitudes and

Dear, I am trying to visualise a time-progressing line (it's supposed to represent spread patterns) using brew package and Google Earth. The idea is to have a function which takes start and end point geographic coordinates, as well as number of intervals to chop the path up, and returns the collection of points segmenting this line. Unfortunately my calculations fail for large distances,

Thanks to the lattice gurus on this list, and having reference to the excellent open-access Sarkar 2008 ISBN 978-0-387-75968-5 e-ISBN 978-0-387-75969-2 http://dx.doi.org/10.1007/978-0-387-75969-2 I now know how to label lattice panels by variable value: see thread starting @ https://stat.ethz.ch/pipermail/r-help/2012-November/329450.html (and demonstrated below). This allows me to use

Hello, I am trying to match lat/lon from one dataset with the lat/lon from a second dataset and use that rows data for calculations. I am using match, but this is finding the first match and not comparing the pair, how can I determine if the lat/lon are the same? See example below. Is there a better way to determine to a matching pair of lat/lon values? Example Datasets: > data2

Dear Users This is my dataset called mydata4. I want to sort the dataframe on the first column PxMid which is basically a column with dates. I've tried mydata4<-mydata4[order(mydata4$PxMid),] but it doesnt work. Could it be because these are dates? Please help I'm really stuck !! Thank you for your time. Regards Meenu PxMid EU0006MIndex.x DMSW1Curncy.x DMSW2Curncy.x DMSW3Curncy.x 1

Hi all, I use kriging to interpolate the precipitation from stations, but the map of this results show lots of stripes. (please see the attachment)I think there's something wrong with the setting of the dimension of this matrix, however, I have no idea how to know or test to see if this setting is correct or not.I've tried to switch the latitude and longitude, but still got the same

Dear all, Does any one knows why should I get the following error message, when trying to do a simple data.frame?? DataF<-data.frame(Subject,BiomR,Spp,Capas,Litter,Herbs,LitterD,MaxCanH,DDifS p,DSSp,Slope, CanDens,NearestSp) Erro em data.frame(Subject, BiomR, Spp, Capas, Litter, Herbs, LitterD, : arguments imply differing number of rows: 202, 0 The data I am using

Hi, I have a set of locations defined by longitude and latitude (in degrees), and want to calculate the spatial (or geographic) distance among all locations. I did not find such a function in the spatial-related packages. (I *cannot* use 'dist', as I have geographic, not cartesian coordinates). thanks! Robert Robert Ptacnik Norwegian Institute for Water Research (NIVA) Gaustadall?en 21

Hi there, I am having some trouble getting download.file to work. I have been searching for the answer but my raw coding ability is not at the same level as the solutions I am getting. I have checked my environment and the proxy settings are in line with what I expected: > Sys.getenv("http_proxy") http_proxy "http://proxy-lon2.macbank" >

Dear Experts, I am new to R and unfortunately cannot start with a simply statistical analysis: I manually determined the volume of the right and left hippocampus in a group of meditators and in a group of controls. My data-sheet looks as follows: observation subject group age gender hemisphere volume 1 am04 m 25 f left 3.637 2 am04 m 25 f right 3.713 3 ao08 m 47 m left 3.715 4 ao08 m 47

Hello, This is what I am trying to do: I wrote a little function that takes addresses (coordinates) as input, and returns the road distance between every two points using Google Maps. Catch is, there are 2000 addresses, so I have to get around 2x10^6 addresses. On my first go, this is what I did: ######################################### getRoadDist = function(X,complete=F){ # X must be a