similar to: Iteration : matrix multiplication / addition

Hey Jarett, 2009/2/24 <jarett.stevens at usermail.com> > After upgrading to the 2.4.1 version, I wasn't able to read as many > variables from my UPS. After a bit of experimentation, I determined that > the firmware on my UPS was different than what is currently in the > apcsmart driver, though it had worked before. I located my firmware > version (5ZM), and added in

I posted this earlier, but am not certain that it was in fact posted, so I will try again. Hi, I have an equation Xcp and would like to look at errors affecting it. I am applying errors of -.58 to .1 to R and -.45 to .47 to Xc. I would like to look at all combinations. I set up a matrix function as follows and it does not work. On the last line, when it run, it does not seem like the two X’s

Hello, I am currently trying to simulate data and analyze it using the frailty option in the coxph function. I am working with recurrent event data, using counting process notation. Occasionally, (about 1 in every 100 simulations) I get the following warning: Error in coxph(Surv(start, end, censorind) ~ binary + uniform + frailty(subject, : X matrix deemed to be singular; variable 2 My

Dear R, I have a simple question concerning with a special case of spare matrix multiplications. Say A is a 200-by-10000 dense matrix. B is a 10000-by-10000 block- diagonal matrix, and each diagonal block B_i is 100-by-100. The usual way I did A%*%B will take about 30 seconds which is to time consuming because I have to do this thousands of times. I also tried to partition A into 100 small blocks

Hi Peter, I've fwded your info to the list, as other people might be interested in. I've also logged a patch tracker so that you can follow its inclusion: https://alioth.debian.org/tracker/index.php?func=detail&aid=302882&group_id=30602&atid=411544 As a side note, there is a work underway to merge the similar driver (mustek, powermust, ...) into one named megatec. This one

Hi listers, I am having some trouble in a matrix multiplication... I have already checked some posts, but I didn't find my problem... I have the following code... But I am not getting the right multiplication... I checked the dimension and they are fine... id_y <- array(1:10,dim=c(2,1,5)) id_yt<-aperm(id_y,c(2,1,3)) m_id<-array(dim=c(dim(id_y)[1],dim(id_y)[1],dim(id_y)[3])) for (i in

(hmmm, finally hitting the Sent button...) 2017-05-24 13:56 GMT+02:00 Jim Klimov <jimklimov at cos.ru>: > On May 24, 2017 1:08:09 PM GMT+02:00, Charles Lepple <clepple at gmail.com> > wrote: > >On May 24, 2017, at 5:11 AM, Arnaud Quette <arnaud.quette at gmail.com> > >wrote: > >> > >> Hi all, > >> > >> here is another one,

Dear R-users, I am searching to the "best" way to compute a series of n matrix multiplications between each matrix (mXm) in an array (mXmXn), and each column of a matrix (mXn). Please find below an example with four possible solutions. The first is a simple for-loop which one might avoid; the second solution employs the tensor product but then manually selects the right outcomes. The

Dear all, Sorry to bother you with such a stupid question, but I just cannot find the solution to my problem. I'd like to use matrix multiplication for meanA and factorial 3. I use the command meanA%*%factorial 3. But everything I get is: Error in factorial3 %*% A : non-conformable arguments I know that the number of the columns of the first vector has to be the same number of rows of the

R Version 2.12.1 (2010-10-15) vs 2.12.0 has slowed down 8 fold for dual core and 17 fold for dual-core-dual-processor Macs. I have checked this result on 3 different macs using the following R-script: Using Version 2.12.0 on a dual core dual processor Mac: > source("http://www.bio.umass.edu/biology/kunkel/pub/R/CuriousResult.R") matrix multiplication 43.543 1.308 14.788

Just to avoid possible confusion, let me correct a typo (at step [2] in the example below). Apologies! -----FW: <XFMail.111023084327.ted.harding at wlandres.net>----- Date: Sun, 23 Oct 2011 08:43:27 +0100 (BST) Sender: r-help-bounces at r-project.org From: (Ted Harding) <ted.harding at wlandres.net> To: r-help at r-project.org Subject: Re: [R] symmetric matrix multiplication On

I'm simulating a Markov process using a vector of proportions. Each value in the vector represents the proportion of the population who are in a particular state (so the vector sums to 1). I have a square matrix of transition probabilities, and for each tick of the Markov clock the vector is multiplied by the transition matrix. To illustrate the sort of thing I mean: pm <-

I have a symmetric matrix B (17x17), and a (17x17) square matrix A. If do the following matrix multiplication I SHOULD get a symmetric matrix, however i don't. The computation required is: C = t(A)%*%B%*%A here are some checks for symmetry > (max(abs(B - t(B)))) [1] 0 > C = t(A)%*%B%*%A > (max(abs(C - t(C)))) [1] 3.552714e-15 Any help on the matter would be very much appreciated.

Hi, A quick bench-mark of an R matrix muliplication 500by500 X 500by10000, all random variates, with matlab reveals a huge difference in speed (5 times at least). Is there anything that can be done in R to speed up the multiplication? Kind regards, Oyvind -- View this message in context: http://r.789695.n4.nabble.com/matrix-multiplication-speed-R-tp3217257p3217257.html Sent from the R devel

Hi Patrick, 2010/11/15 Patrick O'Malley > I've confirmed that the CyberPower CP1350AVRLCD works with nut using > the USB port and the usbhid-ups driver. It is not on your list. > Thanks! > have you checked all variables, and most of all that shutdown works as expected? ie http://new.networkupstools.org/user-manual.html#Testing_shutdowns please also send us an upsc output.

Hi, I have a transition matrix T for which I want to find the steady state matrix for. This could be approximated by taking T^n , for large n. T= [ 0.8797 0.0382 0.0527 0.0008 0.0212 0.8002 0.0041 0.0143 0.0981 0.0273 0.8802 0.0527 0.0010 0.1343 0.0630 0.9322] According to a text book I have T^200 should have reached the steady state L L

Dear All I new to using R and am struggling with some matrix multiplication. I have two matrices, one containing random numbers, these are multiplied together to get another matrix which is different each time. When I put in another for loop to repeat this process a multiple times the matrices are all the same. I?m sure there is a way to keep the randomness of the different matrices but I think

Dear list members, I've got a small question on matrix multiplications in a C code. Because of a really cpu demanding likelihood, I had to use a C code within an R function wrapper. I'm pretty sure that there is already one good code for matrix multiplication in C - maybe in the R source code itself - but I wasn't able to find it. Anyone as an idea on how to handle matrix

Hi all, I am looking for a function like cumprod() that works for matrix multiplication. In other words, I have matrices [M1, M2, ..., Mn], and I want to calculate [M1, M1%*%M2, M1%*%M2%*%M3, ..., M1%*%...%*%Mn] as quickly as possible. Right now I'm using a for() loop but it seems like there should be a faster way. Any help is appreciated! Thanks, Todd Schneider todd.w.schneider@gmail.com

Dear all, I am trying to multiply three different matrices and each matrice is of size 16384,16384 the normal %*% multiplciation operator has not finished one day now. As I am running a system with many cores (and it seems that R is using only one of those) I would like to write fast a brief function that converts the typical for loops of a matrix multiplication to a set of lapply sets (mclapply