similar to: Help: convert entry of a list into a matrix

Dear All, I would like to ask a question on how to find the index of the minimum of entries of a numeric vector, without using loops or user defined functions. Suppose we have a vector: a <- c(3,1,2) then, min(a) = 1 and its index is 2. Target: how to get the index of this minimum? How to get the indices if multiple entries assume this same minimum? Thank you, Chee [[alternative HTML

Dear All, I have a text file, tab delimited, called "sample.txt",as follows: ID_REF 382 GC_Score Theta R B_Allele_Freq Log_R_Ratio 200003 BB 0.9101527 0.9734979 0.8788951 1 0 200006 AB 0.6003323 0.4385073 2.033364 0.4850979 0.01553433 I have explored various options of the command: read.table, with one as:

I have a matrix of 5 columns and 64 rows, let's call it "mat1". All values are 1 or 0. I need to take the values of the elements by row and create a single numeric element that can be placed its respective slot in a 64-element list, named "list1". For example, mat1[11,1:5] = 0,1,1,0,1 and I must put 01101, with a length of 1, into the 11th element of list1. I can create

Hi, How to turn a character string into an unevaluated R object? I want to load some files in a directory into data matrix R objects. I could do this with read.table and assign (see below). Then, I want to turn the character string representing a file name (the evaluated expression of i) into an unevaluated R object. Basically, I want to create matrices whose names are the same as the related file

Dear All, I would like to know, beside writing a function and then apply it to a list, or using a for loop, whether there is a one-line command to do the following. Suppose we have a list, each of whose components are numeric: > a <- vector("list",3) > a[[1]] <-c(1,2) > a[[2]] <-c(3,4) > a[[3]] <- c(5,6) > a [[1]] [1] 1 2 [[2]] [1] 3 4 [[3]] [1] 5 6 Target:

Dear All, I would like to generate m positive real numbers c_i, I=1,...,m, such that (1) c_1 + c_2 + ... + c_m=m, (1) after being ordered into c_1 >= c_2 >= .... >=c_m>0, we have that c_m is of the same order of m^(-1/8), when m is sufficiently large. Thanks, -Chee [[alternative HTML version deleted]]

I guess this has a simple solution: I have matrix 'mat1' which has row and column names, e.g.: A B C row1 0 0 0 row2 0 0 0 .... rown 0 0 0 I have a another matrix 'mat2', essentially a subset of 'mat1' where the rownames are all in 'mat1' e.g.: B row3 5 row8 6 row54 7 I want to insert the values of matrix mat2 for column B (in reality it could be some or

HI, May be this helps: set.seed(24) ?mat1<- matrix(sample(1:60,30*24,replace=TRUE),ncol=24) colnames(mat1)<- rep(c("O","H","L","C"),6) indx<-seq_along(colnames(mat1)) n<- length(unique(colnames(mat1))) ?res<- lapply(split(indx,(indx-1)%%n+1),function(i) mat1[,i]) lapply(res,head,2) #$`1` #????? O? O? O? O? O? O #[1,] 18 56 51 24 24 52 #[2,]

Hello, I have a matrix mat1 of dim [1,8] and mat2 of dim[30,8], I want to replace the first row of mat2 with mat1, this is what I do: mat2[1,]<-mat1 but it transforms mat2 in a list I don't understand, I want it to stay a matrix... ----- Anna Lippel -- View this message in context: http://n4.nabble.com/Simple-question-on-replace-a-matrix-row-tp1427857p1427857.html Sent from the R help

Hi Can someone show me an easy way to multiple a weighted vector with an matrix? example below mat1<-matrix(sample(1:100,80,replace=TRUE),ncol=8) w <- 1/1:10 I want the first element in w to be multiplied by the first row of mat1 and 2nd element in w to be multiplied with the 2nd row and so on. I have huge matrix is there an easy way other than diag(w)%*%mat1 Thanks -- View this

Hello fellow R users, I have a matrix computation that I imagine should be relatively easy to do, however I cannot figure out a nice way to do it. I have two matrices, for example mat1 <- matrix(c(1:5,rep(NA,5), 6:10), nrow=3, byrow=T) mat2 <- matrix(c(2:6, 6:10, rep(NA,5)), nrow=3, byrow=T) I'd like to compute the element-wise average for non-NA entries. Of course (mat1+mat2)/2

Dear all, Ket say I have 3 matrices : mat1 <- matrix(rnorm(16), 4) mat2 <- matrix(rnorm(16), 4) mat3 <- matrix(rnorm(16), 4) Now I want to merge those three matrices to a single one with dimension 4*3=12 and 4 wherein on resulting matrix, row 1,4,7,10 will be row-1,2,3,4 of "mat1", row 2,5,8,11 will be row-1,2,3,4 of "mat2" and row 3,6,8,12 will be row-1,2,3,4 of

Hi all. I do not know if it is a bug in the windows version but i have this problem. Reading a file with 200000 rows, 2 columns and transforming into a 200000 x 2 matrix. If I try to find an element by using the which command which gives some correct indexes plus some others passing the 200000 row boundaries. If I try to reach those "outbound" indexs I get an "Error: subscript out

Dear All, I would like to define a function: f(x,y,z) with three arguments x,y,z, such that: given values for x,y, f(x,y,z) is still a function of z and that I am still allowed to find the root in terms of z when x,y are given. For example: f(x,y,z) = x+y + (x^2-z), given x=1,y=3, f(1,3,z)= 1+3+1-z is a function of z, and then I can use R to find the root z=5. Thank you. -Chee [[alternative

Hello again, Let say I have 2 matrices which equal number of columns but different number of rows like: Mat1 <- matrix(1:20, 4, 5) Mat2 <- matrix(1:25, 5, 5) Now for each column 1-to-5 I need to fetch the corresponding columns of these 2 matrices and add the corresponding elements (ignoring NA values if any). Therefore for the 1st column I need to do: (1+1), (2+2),...,(4+4), (NA+5) and

Dear All, For function: rmvnorm{mvtnorm} in (library mvtnorm, not splus2R), if I generate 2 bivariate normal samples as follows: > rmvnorm(2,mean=rep(0,2),sigma=diag(2)) [,1] [,2] [1,] 2.0749459 1.4932752 [2,] -0.9886333 0.3832266 Where is the first sample, it is stored in the first row or the first column? Does this function store samples row-wise or column-wise? Thank

Dear All, I would like to know how to sort a vector of numeric values such that we know the original index of each ordered component. Say, we have c <- c(1,4,3,2) csort <- sort(c,descreasing=FALSE) With a few components of c, we can manually find out: csort[1] = 1 = c[1], ie, the original index of csort[1] is 1, csort[2] =2 =c[4], ie, the original index of csort[2] is 4. When length(c) is

Dear All, I would like to ask a question on how to do overlay plots in each subgraph of xyplot. 1. I did simulations for m=1000, 2500, 5000, 10000, as the sample sizes. 2. for each sample size value m, 4 graphs are generated; each graph contains overlayed comparisons between 4 methods, 3. now I want put them into a 4-by-4 plot by xyplot, i.e., 4 sample size values, each of which has 4 plots.

Hello my friends, here is a code I wrote with no loops on matrix that is taking too long (2 seconds and I call him 720 times --> 12 minutes): mat1 and mat2 are both matrix with 103 columns and 164 rows. sequence <- matrix(seq(1 : ncol(mat1))) returns <- apply(sequence, 1, function, mat1= mat1, mat2 = mat2, day = 1) function<- function(mat1, mat2, colNb, day){

Dear R heleprs   Suppose I have following data   Scenarios combination_names     series1    series2 Sc1 MAT2 GAU1 7.26554 8.409778 Sc2 MAT2 GAU2 7.438128 8.130275 Sc3 MAT3 GAU1 8.058422 8.06457 Sc4 MAT1 GAU2 8.179855 8.022071 Sc5 MAT3 GAU2 8.184033 8.191831 Sc6 MAT3 GAU2 7.50312 8.232425 Sc7 MAT1 GAU2 7.603291 8.200993 Sc8 MAT1 GAU1 8.221755 8.380097 Sc9 MAT3 GAU2 7.904908