similar to: clump of binary pixels on raster

Sorry, I did not make my question clear. Since I have a point theme with many points, some of them may clump together. the problems here are: 1. how to find clumps in a point theme? 2. the convex-hull extension I found only deal with all the points in a theme at each time? how to make each convex hull around each point clump automatically? Thanks. Xiaohua On 5/12/06, Bob Booth <bbooth

Dear all, How to generate one outline polygon for each point clump? Are there any present functions in ArcView, ArcGIS, R or some freewares? I just had a quick look at the package adehabitat and did not find the function. To my knowledge, I could do it as follows: 1) make a grid map of my study area with cell values = 0; 2) assign 1 to the cells containing at least one point; 3) convert the

Hi, I'm trying to create a new S4 class (myMatrix) which for now just extends dgCMatrix (from package Matrix). Then I want to use "[" which is defined in Matrix. Out of the box with "[" (defined in Matrix) I lose the class information and the result is an object of class dgCMatrix. If I specify a "["-method for myMatrix, it is not used because a signature

HI, The code was working perfectly fine yesterday and today, until half an hour ago.? Couldn't find any problems in the code. Still, I am getting error message. myMatrix <- data.matrix(read.table(text=" Name??????????? Age ANTONY??????? 27 IMRAN????????? 30 RAJ????????????????? 22 NAHAS????????? 32 GEO??????????????? 42 ", header=TRUE)) MinMaxArray? <- data.frame(MIN =

Hello R users, I'm trying to solve an apparently simple problem. I include a matrix in a model formula, and I want then to extract the related coefficients. Basically, I want a function func such that: mymatrix <- cbind(rnorm(10),rnorm(10)) y <- b <- rnorm(10) model <- lm(y ~ b + mymatrix) func(mymatrix,model) which returns only the 3rd and 4th coefficients. I thought to

Dear All, Thanks in advance for any help. I have a square matrix of measures of interactions among individuals and would like to calculate a values from a function (colSums for example) with a single individual (row) excluded in each instance. That individual would be returned to the matrix before the next is removed and the function recalculated. I can do this by hand removing rows based upon

Hi, I have a dataset which has around 138 variables and 30,000 cases. I am trying to calculate a mahalanobis distance matrix for them and my procedure is like this: Suppose my data is stored in mymatrix > S<-cov(mymatrix) # this is fine > D<-sapply(1:nrow(mymatrix), function(i) mahalanobis(mymatrix, mymatrix[i,], S)) Error in solve.default(cov, ...) : system is computationally

Dear R Users, I am writing code to present my output data (I'm using Lattice Package). However, it's essential for me to control space between barchart and legend. I've read the package's specification, but unfortunately I haven't spot the information how to do this. Here's the code I've written: barchart(mymatrix[,1:ncol(mymatrix)],horizontal=FALSE,

Is it somehow possible to use the the predict method of the raster package with a prediction model obtained using caret's train()? / predict(rasterStack, carettrain, filename="...", progress='text', format="BSQ", datatype='INT1U', type='response', overwrite=TRUE) / Thank you -- View this message in context:

Dear all, again i have a problem with special case of dropping lines out of a matrix. i tried the following, where throwout is a vector of length 18 with simple id values that should be compared to any for (k in 1:length(throwout)) { mymatrix=matrix(mymatrix[-(forfact[k]),],ncol=4) } this didnt work and i tried the following to find the error: mymatrix[,1][mymatrix[,1]==throwout[7]]

dear r-users, i have got a problem which i am trying to solve: i have got the following commands: Mymatrix <- matrix(1:9,ncol=3) Z <- list("V1"=c("a","",""),"V2"=c("b","",""),"V3"=c("c","",""),"V4"=c("d","","")) Mymatrix <-

Hello, I have a double matrix that I want to represent in a line chart. Although I have seen some examples I still don't manage to get it. My data is this (a double matrix called mymatrix) : Blogs Wikis Redes Etiq. SPC LMS Menor de 30 57.14 28.57 14.29 28.57 57.14 28.57 de 31 a 40 63.83 61.70 29.79 17.02 59.57 70.21 de 41 a 50 72.64 70.75 47.17 20.75 55.66 75.47 Mayor de

I would write in tab-text file a table like this one: TAB colname1 TAB colname2 TAB TAB... colnameN rowname1 # # # rowname2 # # # rownameM # # # then I wrote something like: mymatrix <- matrix(nrow=M,ncol=N,byrow=T) rownames(mymatrix) <- chvector1 colnames(mymatrix) <- chvector2

Dear list, I would like to subset a large expression matrix based on rownames. That is, I have a list (as a txt-file) with gene names that matches some of the rows in my matrix. I've loaded my matrix as well as gene list using the read.table() command. myMatrix <- read.table("name_of_file.txt", header=T, row.names=1) list_to_keep <- read.table("name_of_file.txt",

Dear all, given I have a data.frame in a format like this mydf <- data.frame(age=rep(1:3,5), year=c(rep(1996,3), rep(1997,3), rep(1998,3), rep(1999,3), rep(2000,3)), income=1:15) mydf Now I convert it to some 2D-frequency table like this: mymatrix <- tapply(X=mydf$income, INDEX=list(mydf$age, mydf$year),

Hello all, I'm new to adehabitat and am having trouble getting my ascii files into the r. I have 45 environmental data layers that are all stored in a folder as ascii files. Is there an easy way to pull in all 45 of my data layers into a kasc dataframe. I'm not new to r or multivariate modeling, but the documentation seems confusing. I've experimented with bringing a few of them in 1

Dear R-Helpers, I have a matrix where the first column is known. The second column is the result of multiplying this first column with a constant "const". The third column is the result of multiplying the second column with "const"..... So far, I did it like this (as a simplified example): nr.of.columns <- 4 myconstant <- 27.5 mymatrix <- matrix(numeric(0), nrow=5,

Hello, I am running a program in r that calls a function, which calls another function, which calls another etc. These functions are of the form: example<- function(x,y,z) {x, y, and z are defined within curly braces like this} Here's my question. To start the main function, I input as an initial parameter a matrix of regressors of the form: MyMatrix<-cbind(this.one,that.one)

Hi, Here, i have a matrix like this MyMatrix <- *DATETIME HEADER1 HEADER2* 1/1/2010 0:10 197.1947 100.0859 1/1/2010 0:20 203.8811 100.1013 1/1/2010 0:30 206.564 100.0433 1/1/2010 0:40 207.9563 99.9393 i want to get the time difference in minutes between two date. TimeDiff <- MyMatrix[1,1] - MyMatrix[2,1] TimeDiff

Hi, I have a dataframe (say myData) and want to get a list (say myList) that contains a matrix for each row of the dataframe myData. These matrices are calculated based on the corresponding row of myData. Using a for()-loop to do this is very slow. Thus, I tried to use apply(). However, afaik apply() does only return a list if the matrices have different dimensions, while my matrices have