similar to: rref() for R

Hi everyone, I am looking to use R as a MATLAB replacement for linear algebra. I've done a fairly good job for finding replacements for most of the functions I'm interested in, I John Fox wrote a program for implementing the reduced row echelon form of a matrix (by doing the Gauss-Jordan elimination). I modified it a bit: rref <- function(A,

I was looking for an R-package that would reduce matrices to row-echelon form, but Google was not my friend; any leads? If not, I wonder if the problem could be expressed in terms of constraint satisfaction...

I think one needs an LU decomposition rather than QR. However, I couldn't find anything off the shelf to do an LU, other than learning that determinant() now uses LU instead of QR or SVD, so the code to do it must be in there for those that want it. You'll probably need to divide rows of U by the first entry if you insist on the unique reduced REF. However, I can't see any reason

Hello I have a 3x3 matrix (A), which I would have to reduce to Reduced Row echelon form.  Besides, at every iteration k, the elementary row matrix Ek has to be printed and also print the product of sum Ei (i=1 to k) and A. Any ideas how to go about doing this. KS. [[alternative HTML version deleted]]

Is there an easy way to do a linear model with an a priori known slope? In essence, I want to minimize the residuals around a line of known slope. -R -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the

People kept reporting NFS issues, specifically getting ESTALE alot. I figured out how to reproduce the problem SERVER mkfs.btrfs /dev/sda1 mount /dev/sda1 /mnt/btrfs-test <add /mnt/btrfs-test to /etc/exports> btrfs subvol create /mnt/btrfs-test/foo service nfs start CLIENT mount server:/mnt/btrfs /mnt/test cd /mnt/test/foo ls SERVER echo 3 > /proc/sys/vm/drop_caches CLIENT ls

I'm interfacing to C code that uses 1-based indexing on arrays -- it ignores the zeroth element. Thus, input vectors from R must be moved up one, and output arrays must be moved down one. What is the best way to deal with this using R internal code? My current approach is: For an input R vector of length n, allocate a new vector(v) of length n+1 and copy input into v[1] to v[1+n]. Call

how to produce a Row Reduced Echelon Form for a matrix in R? Aimin Yan

I'm trying to manipulate/change a formula prior to passing it to another function. A simplified example: User passes formula to my function: y~x My function does: lm(transform(y)~x) Here, transform() is added to the model's response. What is the best way to accomplish this?

Hi all, I am trying to compile a fortran routine originally written for R from within matlab. It all worked fine, but the newest version of the Fortran code has a call to rchkusr() and I now get a message that this is an undefined symbol. I am under the impression that rchkusr() just serves to let the processor take care of interruption messages (typically, the user frantically

Sorry for the cross post, but I can't find the original mail I don't know if it was sent to the OpenAFS or the Samba list... I've managed to fix some compilation/build problems when using '--with-afs' to Samba. Something about undefined attributes: ----- s n i p ----- Linking bin/smbd lib/afs.o: In function `afs_createtoken':

Hi, All: How might one test Matlab and perl code during "R CMD check"? I ask for two reasons: First, the "fda" package exists in both R and Matlab, and it would help if we could run test examples in Matlab as part of "R CMD check". I tried "R.matlab", but could not get it to work in that context. Second, I have professional

I'd trying to subclass the "lm" class to produce a "mylm" class whose instances behave like lm objects (are accepted by methods like summary.lm) but have additional data or slots of my own design. For starters: setClass("mylm", "lm") produces the somewhat cryptic: Warning message: Old-style (``S3'') class "mylm" supplied as a

Hi, I have recently started using R again (switched from MatLab) and have a question regarding programming. How can I set up a file that will run several lines of R code? For example, in Fortran and DOS this used to be done via a batch file, and in MatLab I would write the code and save it in a script file, e.g., Test.m. An example of what I am trying to do is the following:

Hello all, A colleague at work set me the challenge to convert some MATLAB code into R, to see which is faster. We'd seen that benchmark comparing MATLAB 6.5 to R1.90 (and others), and so I thought that I should be able to get roughly comparable speeds. The code has lots of multiplications of matrixes, transposes, and MATLAB's "repmat". I did the code conversion, and R was about

Hi, I have to R fairly recently from Matlab, where I have been used to organising my own custom functions into directories which are adding to the Matlab search path. This enables me to call them as I would one of Matlab's built-in functions. I have not found a way of doing the same thing in R. I have resorted to using source() on symlinks located in the current directory. Not very

Hi, I have been brought back to the "R-Side" from MatLab. I have used R in graduate econometrics but only for statistics and regression (linear and nonlinear). But now I need to run general nonlinear optimization. I know about the add-in quadprog but my problem is not QP. My problem is a general nonlinear (obj funct) with linear constraints.I know about the "ms" and

I'm finding that omindex is consistently ending prematurely when indexing certain files. The last output looks like this: [Entering directory /compounds/Acetic_acid] Indexing "/MATLAB/compounds/Acetic_acid/AACID_50T.TXT" as text/plain ... added. Indexing "/MATLAB/compounds/Acetic_acid/AACID_50T.pdf" as application/pdf ... "pdftotext -enc UTF-8

Hello, I'm looking at porting code written for Matlab to R. However, I don't have sufficient knowledge of Matlab to know whether it's feasible or appropriate. If there is anyone who has any experience in this and could provide some advice, I'd be grateful. TIA, Peter [[alternative HTML version deleted]]

Dear R-help, I have a matrix of data values specified in polar coordinates, i.e. (r,theta). I know that I can transform this image to Cartesian coordinates and then use image to display the results, however, I want to display the image as is, without any coordinate transformations. This would require displaying individual "pieces of pie" colour-coded by their data value. A comparable