similar to: Converting Data Types

Hi, I tried to compute maximum likelihood under gamma distribution, using nlm function. The code is this: __BEGIN__ vsamples<- c(103.9, 88.5, 242.9, 206.6, 175.7, 164.4) mlogl <- function(alpha, x) { if (length(alpha) > 1) stop("alpha must be scalar") if (alpha <= 0) stop("alpha must be positive") return(- sum(dgamma(x, shape = alpha, log = TRUE)))

Dear all, How can I compute the log likelihood of a gamma distributions of a vector. I tried the following. But it doesn't seem to work: samples<-c(6.1, 2.2, 14.9, 9.9, 24.6, 13.2) llgm <- dgamma(samples, scale=1, shape=2, log = TRUE) It gives [1] -4.291711 -1.411543 -12.198639 -7.607465 -21.397254 -10.619783 I expect it only returns "one" value instead of vector.

Hi all, I have this figure: http://docs.google.com/Doc?id=df5zfsj4_103rjt2v4d5 created with the following steps: > x [1] 90.4 57.8 77.0 103.7 55.4 217.5 68.1 85.3 152.0 113.0 97.1 89.9 [13] 68.1 83.7 77.4 34.5 104.9 170.3 88.6 88.1 108.8 77.4 85.6 82.7 [25] 81.3 108.0 49.5 71.0 85.7 99.3 203.5 275.9 51.1 84.8 16.5 72.6 [37] 160.5 158.3 136.7 140.0 98.4 116.1

#using "rollapply" to calculate a moving sum or running sum? #I am tryign to use rollapply to calcualte a moving sum? #I tried rollapply and get the error message #"Error in seq.default(start.at, NROW(data), by = by) : # wrong sign in 'by' argument" #example: mymatrix <- ( matrix(data=1:100, nrow=5, ncol=20) ) mymatrix_cumsum <- ( matrix(data=NA, nrow=5,

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

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, If a matrix with 5 columns has been defined and the first two columns need to be sorted in ascending order, how can this be achieved whilst ensuring the other 3 columns data are in relative position to the sorted columns? Glen Jones [[alternative HTML version deleted]]

I have two objects, one matrix and one vector. I want to use my vector to subset certain values out of my matrix. For example: I want to tell R, to select out all rows in myMatrix into a new myMatrix2 IF that corresponding row is less than a 0.5 in myVector. So: myMatrix = a matrix of 8000 by 20 myVector = vector of 8000 myMatrix2 = a matrix of < 8000 by 20 (based on selection criteria in

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

Hi, Here i have a Matrix MyMatrix <- Name Age --------- ------- ANTONY 27 IMRAN 30 RAJ 22 NAHAS 32 GEO 42 and here i have an array with Minimum and Maximum values. MinMaxArray <- data.frame(MIN = 25,MAX=35) MIN MAX ------ -------- 25 35

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 =

I would like to compare every column in my matrix with every other column and get the r-squared. I tried using the following formula and looping through every column: > summary(lm(matrix[,x]~matrix[,y]))$r.squared If I have 10,000 columns, the loops (10,000 * 10,000) take forever even if there is no formula inside. Then, I attempted to vectorize my code: > cor(matrix)^2 With 10,000

I am trying to find out if R can recognize specific criteria for removing rows (i.e. a prexisting function) I have a matrix myMatrix that is 12000 by 20 I would like to remove rows from myMatrix that have: -999 across all columns -999 across all columns but one -999 across all columns but two -999 across all columns but three -999 across all columns but four -999 across all columns but five

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 everyone, I was trying to do some distribution fitting with a numerical field called Tolls. The sample size = 999 rows. Basically I assigned the Toll data to a new variable K by doing: k<-dtest$Toll After that, tried to fit a gamma distribution by doing: fitG<-fitdist(k, "gamma") Then the following messages showed (oh and I checked for empty rows before doing this):

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 all, I have a variable that I would like also to use it as a string. The reasons is that I want to collect results from different function to one table.. So when I use the  colnames(mymatrix) <-c(function1.function2,function3) the function1, function2, function3 to be "converted" to simple strings so as  colnames(mymatrix)

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,

Dear all, given I have data in a data.frame which indicate the number of people in a specific year at a specific age: n <- 10 mydf <- data.frame(yr=sample(1:10, size=n, replace=FALSE), age=sample(1:12, size=n, replace=FALSE), no=sample(1:10, size=n, replace=FALSE)) Now I would like to make a matrix with (in this simple example) 10 columns (for the

Dear list, I have two functions created in the same environment, fun1 and fun2. fun2 is called by fun1, but fun2 should use an object which is created in fun1 fun1 <- function(x) { ifelse(somecondition, bb <- "o", bb <- "*") ## mymatrix is created, then myresult <- apply(mymatrix, 1, fun2) } fun2 <- function(idx) { if (bb == "o) { #