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Dear all I am so glad the R can provide the efficient calculate about eigenvector and eigenvalue. However, i have some puzzle about the procedure of eigen. Fristly, what kind of procedue does the R utilize such that the eigen are obtained? For example, A=matrix(c(1,2,4,3),2,2) we can define the eigenvalue lamda, such as det | 1-lamda 4 | =0 | 2 3-lamda | then

Hi, I am using eigen to get an eigen decomposition of a square, symmetric matrix. For some reason, I am getting a column in my eigen vectors (the 52nd column out of 601) that is a column of all NAs. I am using the option, symmetric=T for eigen. I just discovered that I do not get this behavior when I use the option EISPACK=T. With EISPACK=T, the 52nd eigenvector is (up to rounding error) a

I have been looking at the "eigen" function and have reintroduced the ability to compute (right) eigenvalues and vectors for non-symmetric matrices. I've also made "eigen" complex capable. The code is based on the eispack entry points RS, RG, CH, CG (which is what S appears to use too). The problem with both the S and R implementations is that they consume huge amounts

Hi all, Recently our statistics students noticed that their Gibbs samplers were crashing due to some NaNs in some parameters. The NaNs came from mvrnorm (Ripley & Venables' MASS package multivariate normal sampling function) and with some more investigation it turned out that they were generated by function eigen, the eigenvalue computing function. The problem did not seem to happen

Dear subscribers of R-devel I am experiencing that R crashes (further details are given below) in some complex matrix calculations when EISPACK=TRUE has been specified in eigen(). I discovered the behaviour some months ago just after the release of R-2.2.0, and it has been lying on my desk since. I apologise for not having nailed the problem down to a simple function call, but I thought I

---------- Forwarded message ---------- From: Shubha Vishwanath Karanth <shubhak at ambaresearch.com> Date: Nov 24, 2006 7:54 PM Subject: Dates Conversion/write.foreign To: Shubha Karanth <shubhakaranth at gmail.com>, Shubha Vishwanath Karanth <shubhak at ambaresearch.com> Hi R experts, I need an urgent help... I have an a dataframe caled idat. Below i give a snapshot

Hi R, This is a very trivial one.... C=0.1 I want to check whether my value of C is between 0 and 1 exclusively.... I don't want to use (C>0 & C<1). And I can't use a single statement like (0<C<1). Is there a between function? Or how do we specify from 0 to 1? Does %in% help me? Many Thanks, Shubha This e-mail may contain confidential and/or

Hi R, I need to generate 50 random numbers (preferably poisson), such that their sum is equal to 100. How do I do this? Thank you, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}

Hi R, Let, x=1:80 I want to sum up first 8 elements of x, then again next 8 elements of x, then again another 8 elements..... So, my new vector should look like: c(36,100,164,228,292,356,420,484,548,612) I used: aggregate(x,list(rep(1:10,each=8)),sum)[-1] or rowsum(x,group=rep(1:10,each=8)) But without grouping, can I achieve the required? Any other ways of doing

Hi R, This is a cross tabulation question. Suppose that, > d=read.table("clipboard",header=F) > d V1 V2 V3 A One Apple A One Cake A One Cake B One Apple B One Apple B One Apple > table(d$V2,d$V3) Apple Cake One 4 2 But, I don't want the count to be like the above. Here, it is counting the

Hi R, If x=c(1,3,5) y=c(2,4,6) I need a vector which is c(1,2,3,4,5,6) from x and y. How do I do it? I mean the best way.... Thanks, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}

Hi R, Can I get a comparison between R and MATLAB? How is R efficient than MATLAB? Or what are the weaknesses of R compared to MATLAB? Thank you very much for your help, Shubha Shubha Karanth | Amba Research Ph +91 80 3980 8031 | Mob +91 94 4886 4510 Bangalore * Colombo * London * New York * San José * Singapore * www.ambaresearch.com This e-mail may contain confidential and/or

Hi R, I am trying to download the data from R. I give the below command. > library(fImport) > yahooSeries("IBM") trying URL 'http://chart.yahoo.com/table.csv?s=IBM&a=7&b=08&c=2007&d=7&e=07&f=2008& g=d&x=.csv' Error in download.file(url = url, destfile = file, method = method) : cannot open URL

Hi R, I have a list, l=list(list(c(1,2),c(4,5),c(6,7)),list(c(11,22,33),c(44,55,66))) > l [[1]] [[1]][[1]] [1] 1 2 [[1]][[2]] [1] 4 5 [[1]][[3]] [1] 6 7 [[2]] [[2]][[1]] [1] 11 22 33 [[2]][[2]] [1] 44 55 66 How do I know the dimensions of this list?... In other words, how many sub-lists, sub-sub-lists etc...are there in l? How do I know this?

Hi R, Can I transpose a data frame by a particular group variable? For example: d=data.frame(group=c(1,1,2,2,2),val=c(6,4,6,3,5)) And my output should be: data.frame(group=c(1,2),v1=c(6,6),v2=c(4,3),v3=c(NA,5)) Many thanks, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}

Hi, Suppose a=matrix(1:9,3,3) > a [,1] [,2] [,3] [1,] 1 4 7 [2,] 2 5 8 [3,] 3 6 9 Now, > class(a[1:2,]) [1] "matrix" > class(a[1:3,]) [1] "matrix" > class(a[,1:2]) [1] "matrix" > class(a[,1:3]) [1] "matrix" But, > class(a[1,]) [1] "integer" > class(a[,1]) [1]

Hi, Could anyone tell me what is the command used in R to do 1. Differentiation 2. Newton Raphson method (Numerical Analysis in general...) Are there any packages separately for this? Thanks for your help! BR, Shubha [[alternative HTML version deleted]]

Dear all, I am currently working on the calculation of eigenvalues (and -vectors) of large matrices. Since these are mostly sparse matrices and I remember some specific functionalities in MATLAB for sparse matrices, I started a research how to optimize the calculation of eigenvalues of a sparse matrix. The function eigen itself works with the LAPACK library which has no special handling for

Hi R, I have a an excel file with a lot of data. I need to create an user interface in R, which has one single screen. It needs to contain a right pane containing the click buttons for different countries (say). If the user clicks a country, then a chart needs to be created for that country, taking the data from Excel. Is this possible and which package helps me in doing this? Many thanks in

Hi R, A quick question: How do we find the number of words in a string? Example: C="Have a nice day" And the number of words should be 4. any built in function or?... Thanks, Shubha Shubha Karanth | Amba Research Ph +91 80 3980 8031 | Mob +91 94 4886 4510 Bangalore * Colombo * London * New York * San José * Singapore * www.ambaresearch.com This e-mail may contain