similar to: spare matrix replacing values efficiently

Displaying 20 results from an estimated 3000 matches similar to: "spare matrix replacing values efficiently"

2010 Aug 09
2
efficient matrix element comparison
It is a simple problem in that I simply want to convert the For loop to a more efficient method. It simply loops through a large vector checking if the numeric element is not equal to the index of that element. The following example demonstrates a simplified example: > rows <- 10 > collusionM <- Matrix(0,10,10,sparse=TRUE) > matchM <- matrix(c(1,2,3,4,4,6,7,9,9,10)) > >
2010 Jan 30
2
aggregate by factor
I have a data frame with two columns, a factor and a numeric. I want to create data frame with the factor, its frequency and the median of the numeric column > head(motifList) events score 1 aeijm -0.25000000 2 begjm -0.25000000 3 afgjm -0.25000000 4 afhjm -0.25000000 5 aeijm -0.25000000 6 aehjm 0.08333333 To get the frequency table of events: > motifTable <-
2010 Jan 04
4
function in aggregate applied to specific columns only
I want to use aggregate with the mean function on specific columns gender <- factor(c("m", "m", "f", "f", "m")) student <- c(0001, 0002, 0003, 0003, 0001) score <- c(50, 60, 70, 65, 60) basicSub <- data.frame(student, gender, score) basicSubMean <- aggregate(basicSub, by=list(basicSub$student), FUN=mean, na.rm=TRUE) This
2010 Jun 15
4
shifted window of string
basically I need to create a sliding window in a string. a way to explain this is: > v <-
2009 Apr 04
2
data.frame, converting row data to columns
I have a data frame something like: name wrist nLevel emot 1 4094 3.34 1 frustrated 2 4094 3.94 1 frustrated 3 4094 NA 1 frustrated 4 4094 3.51
2006 Dec 19
1
preserving sparse matrices (Matrix)
Hi, I have sparse (tridiagonal) matrices, and I use the Matrix package for handling them. For certain computations, I need to either set the first row to zero, or double the last row. I find that neither operation preserves sparsity, eg > m <- Diagonal(5) > m 5 x 5 diagonal matrix of class "ddiMatrix" [,1] [,2] [,3] [,4] [,5] [1,] 1 . . . . [2,] . 1
2012 Dec 11
1
Dispatching on a dgCMatrix does not work.
I represent a graph as an adjacency matrix of class "dgCMatrix" (from the Matrix package). > xx 5 x 5 sparse Matrix of class "dgCMatrix" a b c d e a . 1 1 . . b 1 . 1 . . c 1 1 . 1 1 d . . 1 . 1 e . . 1 1 . To check if the matrix defines and undirected graph, I have made the following functions/methods: is.UG <- function (object) { UseMethod("is.UG") }
2009 Jul 20
1
S4 method dispatch with inheritance
Hi, I'm trying to create a new S4 class (myMatrix) which for now just extends dgCMatrix (from package Matrix). Then I want to use "[" which is defined in Matrix. Out of the box with "[" (defined in Matrix) I lose the class information and the result is an object of class dgCMatrix. If I specify a "["-method for myMatrix, it is not used because a signature
2006 Jul 09
1
package:Matrix handling of data with identical indices
In the Matrix package v. 0.995-11 I see that the dgTMatrix Class for compressed, sparse, triplet-form matrices handles Identically indexed data instances by summing their values, e.g., library(Matrix) (Mt <- new("dgTMatrix", i = as.integer(c(0,0,1,1,4)), j = as.integer(c(0,1,2,2,4)), x = as.double(1:5), Dim = as.integer(c(5,5)))) ## 5 x 5 sparse Matrix of class
2006 Jul 09
1
package:Matrix handling of data with identical indices
In the Matrix package v. 0.995-11 I see that the dgTMatrix Class for compressed, sparse, triplet-form matrices handles Identically indexed data instances by summing their values, e.g., library(Matrix) (Mt <- new("dgTMatrix", i = as.integer(c(0,0,1,1,4)), j = as.integer(c(0,1,2,2,4)), x = as.double(1:5), Dim = as.integer(c(5,5)))) ## 5 x 5 sparse Matrix of class
2012 Jul 28
1
Creating sparse matrix of type "dgCMatrix" directly
I want to create a sparse matrix of type "dgCMatrix" using the Matrix package (and the matrix must be of this type even if other more compact representations may exist). I do > library(Matrix) > m1<-Matrix(rep(1,4),nrow=2,ncol=2,sparse=T) > m1 2 x 2 sparse Matrix of class "dsCMatrix" [1,] 1 1 [2,] 1 1 To convert m1, I do > as(m1, "dgCMatrix")
2017 Oct 20
0
What exactly is an dgCMatrix-class. There are so many attributes.
Subsetting using [] vs. head(), gives different results. R code: > head(train$data, 5) [1] 0 0 1 0 0 > train$data[1:5, 1:5] 5 x 5 sparse Matrix of class "dgCMatrix" cap-shape=bell cap-shape=conical cap-shape=convex [1,] . . 1 [2,] . . 1 [3,] 1 .
2017 Oct 20
0
What exactly is an dgCMatrix-class. There are so many attributes.
> On Oct 20, 2017, at 11:11 AM, C W <tmrsg11 at gmail.com> wrote: > > Dear R list, > > I came across dgCMatrix. I believe this class is associated with sparse > matrix. Yes. See: help('dgCMatrix-class', pack=Matrix) If Martin Maechler happens to respond to this you should listen to him rather than anything I write. Much of what the Matrix package does appears
2017 Oct 21
1
What exactly is an dgCMatrix-class. There are so many attributes.
> On Oct 21, 2017, at 7:50 AM, Martin Maechler <maechler at stat.math.ethz.ch> wrote: > >>>>>> C W <tmrsg11 at gmail.com> >>>>>> on Fri, 20 Oct 2017 15:51:16 -0400 writes: > >> Thank you for your responses. I guess I don't feel >> alone. I don't find the documentation go into any detail. > >> I also find
2016 Apr 19
2
Matrix: How create a _row-oriented_ sparse Matrix (=dgRMatrix)?
Using the Matrix package, how can I create a row-oriented sparse Matrix from scratch populated with some data? By default a column-oriented one is created and I'm aware of the note that the package is optimized for column-oriented ones, but I'm only interested in using it for holding my sparse row-oriented data and doing basic subsetting by rows (even using drop=FALSE). Here is what I
2017 Oct 21
0
What exactly is an dgCMatrix-class. There are so many attributes.
>>>>> C W <tmrsg11 at gmail.com> >>>>> on Fri, 20 Oct 2017 15:51:16 -0400 writes: > Thank you for your responses. I guess I don't feel > alone. I don't find the documentation go into any detail. > I also find it surprising that, >> object.size(train$data) > 1730904 bytes >>
2017 Oct 20
4
What exactly is an dgCMatrix-class. There are so many attributes.
Thank you for your responses. I guess I don't feel alone. I don't find the documentation go into any detail. I also find it surprising that, > object.size(train$data) 1730904 bytes > object.size(as.matrix(train$data)) 6575016 bytes the dgCMatrix actually takes less memory, though it *looks* like the opposite. Cheers! On Fri, Oct 20, 2017 at 3:22 PM, David Winsemius
2012 Oct 09
1
converting dgCMatrix to regular matrix
Hi: I've looked around and I must be missing it because it's probably somewhere. Does someone know how to convert an object of class dgCmatrix to a regular matrix. I can send someone the data if they need it but it's too big to include here. I read the data in using temp<-readMat("movielens.mat") where readMat is from the R.matlab package. But the resulting 2 matrices
2008 Jan 30
1
R package Matrix failing to build with R-devel on Ubuntu AMD64
Switched back to R-devel tonight after using R-2.6.1 for awhile and when I updated my devel packages Matrix installation failed. Not critical for me but thought I should report it. I am using Ubuntu Gusty AMD64 OS. Tail of install output and sessionInfo follows. Mark Loading required package: methods Loading required package: lattice Attaching package: 'Matrix' The
2004 Aug 06
1
YP submission / cURL issue. (icecast 2.0.1 / gentoo)
Karl Heyes wrote: > The libs that Brendan mentioned are loaded after the start of the > program, in fact they are referenced when the host name is looked up. > The loading is done within libc so apps like icecast don't know it's > being done. ldd does not show these libs, but the mechanism is the same > as used by plugins of various apps. Would building statically help? Is