similar to: row*matrix

Hi all: Thanks in advance for your assistance. I just started learning R. I'm trying to use the Help and the downloadable manuals. I am stuck on trying to multiply matrices. Can anyone please supply a couple of lines of code that I can plug into a fresh console to see how a double precision (1x3) matrix is multiplied by a double precision (3x3) matrix? I keep getting an error

is there a way to do element-by-element multiplication as in Gauss and MATLAB, as shown below? Thanks. --- a 1.0000000 2.0000000 3.0000000 x 1.0000000 2.0000000 3.0000000 2.0000000 4.0000000 6.0000000 3.0000000 6.0000000 9.0000000 a.*x 1.0000000 2.0000000 3.0000000 4.0000000

I have a big matrix 'ret'. I want to multiply each row of it with a 2nd vector 'pos', resulting result, I want to save in a vector named 'port'. I wrote following code: > pos [1] 2593419 2130220 6198197 1673888 1980000 1784732 2052120 -7490228 -5275000 > dim(ret) [1] 500 9 > fu # user defined function function(x) { fu = x %*%

In my code, I calculate the maximum values with 2 factors using maxr=with(arrdf, tapply(rate,list(weekday,quarter), max, na.rm=T)) and I want to write out the file so that Excel can read it. I used write.table(maxr, fname, sep=",", col.names=TRUE, row.names=TRUE, quote=TRUE, na="0") which works, and yields something like

Hello useRs, I'd like to perform a moving average on the dataset, xx. I've tried combining the functions Reduce and rollmean but it didn't work. > r <- function(n) rollmean(n, 2) # where 2 = averaging interval > output < - Reduce("r", x) Error in f(init, x[[i]]) : unused argument(s) (x[[i]]) Is there anything wrong with the code in the first place? where

Hi all, I am trying to multiply each column of a matrix such to have a unique resulting vector with length equal to the number of rows of the original matrix. In short I would like to do what prod(.) function in Matlab does, i.e. A <-matrix(c(1:10),5,2) V = A[,1]*A[,2] Thank you Graziano [[alternative HTML version deleted]]

I used to consider using R and "Optim" to replace my commercial packages: Gauss and Matlab. But it turns out that "Optim" does not converge completely. The same data for Gauss and Matlab are converged very well. I see that there are too many packages based on "optim" and really doubt if they can be trusted! -- View this message in context:

Dear R Users, I have a data frame of 360 rows by 720 columns (259200 values). For each value in this grid I am hoping to apply an equation to, to generate a new grid. One of the parts of the equation (called 'p') relies on reading from a separate reference table. This is Table 4 at: http://www.fao.org/docrep/s2022e/s2022e07.htm#3.1.3%20blaney%20criddle%20method (scroll down a little).

Is there an element-by-element multiplication in R, like the .* operator in Matlab? eg: A (2x3) B (2x3) C=A.*B C (2x3) C = [[a11*b11 a12*b12 a13*b13]; [a21*b21 a22*b22 a23*b23]] I can't find one... Thanks -Mike Gates

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

I submit the following matrix to both MATLAB and R x= 0.133 0.254 -0.214 0.116 0.254 0.623 -0.674 0.139 -0.214 -0.674 0.910 0.011 0.116 0.139 0.011 0.180 MATLAB's inv(x) provides the following 137.21 -50.68 -4.70 -46.42 -120.71 27.28 -8.94 62.19 -58.15 6.93 -7.89 36.94 8.35 11.17 10.42 -14.82 R's solve(x) provides: 261.94 116.22 150.92 -267.78 116.22 344.30 286.68

I was able to do a cheap workaround By putting this: this.editField.focus(); at the end of the enterEditMode: function() this still does not allow highlighting with the mouse. Also if there are regular forms in a draggable the end user is screwed especially when using firefox. -----Original Message----- From: Stephen Major [mailto:smajor@gmail.com] Sent: Thursday, September 01, 2005 3:28 AM

Hi Everyone, To complete the outer() and kronecker() functions in the base, may I suggest the following tensor() function, which allows the multiplication of arrays through sets of conformable dimensions. I am happy to write a help page if required. The code also needs a setdiff() function which prompts me to ask: what about simple set functions? I expect many of us have written our own

Hello, I have noticed that when an In-place editor is inside a Draggable in IE it is real sketchy, cannot highlight text and plain out cannot edit in Firefox. Respectfully, Stephen

I have own function wrote. I used an algorithm, which was written in Matlab. in matlab: ... gamma = inv(v)*g; ... #v = matrix of variable size, v=vv(k) => k=2 => dimension of v 2x2 #g = a line vector with 4 elements e.g. g=[1,0,2,0]; my rewritten r-file: ... gamma = solve(v)*g; ... which is my error? Who can help me? thank you in advance. Chris -- Lust, ein paar Euro nebenbei zu

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

Hi Zhoulai, I am trying to modify "LoopUnrollPass" in llvm which produces multiple copies of loop equal to the loop unroll factor.Currently, using multicore architecture, say 3 for example and the execution goes like: for 3 cores if there are 9 iterations of loop core instruction 1 0,3,6 2 1,4,7 3 2,5,8 But I want to to

I'm very new to R and utterly blown away by not only the language but the unbelievable set of packages and the documentation and the documentation standards and... I was an early APL user and never lost my love for it and in R I find most of the essential things I loved about APL except for one thing. At this early stage of my learning I can't yet determine if there is a way to

Dear list members, I need to translate 3 lines of matlab code to R (a loop, to be specific), and I don't know what would be the results in matlab or how to do it in R-- I don't realise if they are doing to the col, vector or what. if the results are a vector or a value or a matrix :-( Anyone with matlab, can run it and give me the result? Any ideias what am I doing wrong? The code is

Hello R-helpers, What I have: I am working with vectors not matrice: #Basic equations A <-c(-20,-9,-2) x <-c(0.17,0.22,0.61) B <- crossprod(A,x) # R matrix multiplication works with vectors A%*%x==B # Is true... Question: If x is unknown and A and B are known, how do I solve for x in R? solve(A,B) won't work because A is not a square matrix solve(A,B) Error in solve.default(A,