similar to: R wildcards, sapply and as.factor

Displaying 20 results from an estimated 700 matches similar to: "R wildcards, sapply and as.factor"

2005 Nov 09
8
Element-by-element multiplication operator?
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
2007 Mar 10
3
long character string problem
Hi All I am having 2 very long character strings (550chars) and I want to put them as expressions together with c(). The problem is that I also get these double-quotes, as seen below in 'fct'. How can I remove these double-quotes? I tried as.name() but it did not work (because of size?). These are creating trouble with subsequent programs, which I tested with strings that for some
2008 Nov 29
2
Reading mixed tables
Dear R buddies, This weekend I became interested in solving Google Code Jam problems using R. I guess R may work very well in this kind of contests but the input of file has been a problem for me. Take this case for example (http://code.google.com/codejam/contest/dashboard?c=agdjb2RlamFtchALEghjb250ZXN0cxjRzBQM), the files are usually of the form: A(number of lines for group 1) a11 a12 a13 a21
2010 Apr 13
1
Lapack, determinant, multivariate normal density, solution to linear system, C language
r-devel list, I have recently written an R package that solves a linear least squares problem, and computes the multivariate normal density function. The bulk of the code is written in C, with interfacing code to the BLAS and Lapack libraries. The motivation here is speed. I ran into a problem computing the determinant of a symmetric matrix in packed storage. Apparently, there are no explicit
2007 Nov 16
4
Permutation of a distance matrix
Hi there, I would like to find a more efficient way of permuting the rows and columns of a symmetrical matrix that represents ecological or actual distances between objects in space. The permutation is of the type used in a Mantel test. Specifically, the permutation has to accomplish something like this: Original matrix addresses: a11 a12 a13 a21 a22 a23 a31 a32 a33 Example
2012 Mar 28
6
How to get all possible combinations?
Dear all, suppose I have a vector with elements as: Vec <- c(2,3,4,5,6) Now I want to have all possible combination of length 3 using those elements and without any repetition. Like, I want to have 1 possibility like 2-3-4 but not 3-2-4. Can somebody guide me how to achieve that in R? Thanks for your help.
2009 Jul 10
3
strange strsplit gsub problem 0 is this a bug or a string length limitation?
I was working with the rmetrics portfolioBacktesting function and dug into the code to try to find why my formula with 113 items, i.e. A1 thru A113, was being truncated and I only get 85 items, not 113. Is it due to a string length limitation in R or is it a bug in the strsplit or gsub functions, or in my string? I'd very much appreciate any suggestions ============Input script:
2006 Dec 31
7
zero random effect sizes with binomial lmer
I am fitting models to the responses to a questionnaire that has seven yes/no questions (Item). For each combination of Subject and Item, the variable Response is coded as 0 or 1. I want to include random effects for both Subject and Item. While I understand that the datasets are fairly small, and there are a lot of invariant subjects, I do not understand something that is happening
2004 Jul 03
1
solving for a 2D transformation matrix
We have recently digitized a set of points from some scanned engineering drawings (in the form of PDFs). The digitization resulted in x,y page coordinates for each point. The scans were not aligned perfectly so there is a small rotation, and furthermore each projection (e.g. the yz-plane) on the drawing has a different offset from the page origin to the projection origin. From the dimensions
2009 May 19
4
nlrwr package. Error when fitting the optimal Box-Cox transformation with two variables
Dear all: I'm trying to fit the optimal Box-Cox transformation related to nls (see the code below) for the demand of money data in Green (3th Edition) but in the last step R gives the next error message. Error en `[.data.frame`(eval(object$data), , as.character(formula(object)[[2]])[2]) : undefined columns selected. ?Any idea to solve the problem? Thanks in advance,
2006 Mar 18
1
Search for the minimum of a fitted curve
Hi, I have a function of the second grade, with 2 parameters: y~A^2 + A + B^2 + B The response y is a measurement for the precision of the analytical method, where A en B are method parameters. As its neccesary to keep the precision of the analytical methad as good as possible, its usefull to optimize A en B to keep y as low as possible. But how can I do this with R? I have searched the
2008 Jun 23
3
Simulating Gaussian Mixture Models
Hi, Is there any package that I can use to simulate the Gaussian Mixture Model , which is a mixture modeling method that is widely used in statistical learning theory. I know there is a mclust, however, I think it is a little bit different from my problem. Thanks very much.. regards. -------------------------- Peng Jiang ?? Ph.D. Candidate Antai College of Economics &
2010 Jan 07
1
faster GLS code
Dear helpers, I wrote a code which estimates a multi-equation model with generalized least squares (GLS). I can use GLS because I know the covariance matrix of the residuals a priori. However, it is a bit slow and I wonder if anybody would be able to point out a way to make it faster (it is part of a bigger code and needs to run several times). Any suggestion would be greatly appreciated. Carlo
2005 Jun 14
1
Matrix stability problem
Hello, This is not a problem with R, the calculated results are mathematically correct. This a matrix stability problem. Because of measuring errors, my matrix solution is a bit off. Here is what my equations look like: A11 x11+A12 x12 +A13 x13 = b1 A21 x21+A22 x21 +A23 x23 = b2 A31 x31+A32 x31 +A33 x33 = b3 A is a reading, X is a measured weight, and b is total. The 3 experiments give
2011 Jul 04
1
placing multiple rows in a single row
Dear people from the R help list, I have a question that I can't get my head around to start answering, that is why I am writing to the list. I have data in a format like this (tabs might look weird): John A1 1 0 1 John A2 1 1 1 John A3 1 0 0 Mary A1 1 0 1 Mary A2 0 0 1 Mary A3 1 1 0 Peter A1 1
2013 Apr 22
7
Multiple lon lat points in the map with ggplot2
Hello R users, For the last few days I am struggling with the following task: my data.frame: A1 A2 A3 B1 B2 B3 58.81 53.292 54.501 13.013 17.39 19.407 56.02 56.251 54.033 20.099 13.15 10.411 55.376 53.099 57.625 13.396 21.031 13.22 58.584 53.194 54.218 13.038 16.854 19.289 55.7 55.921 53.847 19.942 13.153 9.828 55.093 52.934
2008 Sep 09
1
creating table of averages
Dear Colleagues, I have a dataframe with variables: [1] "ID" "category" "a11" "a12" "a13" "a21" [7] "a22" "a23" "a31" "a32" "b11" "b12" [13] "b13" "b21"
2013 Feb 01
2
Nested loop and output help
Hello Everyone, My name is Thomas and I have been using R for one week. I recently found your site and have been able to search the archives of posts. This has given me some great information that has allowed me to craft an initial design to an inquiry I would like to make into the breakdown of McNemar's test. I have read an intro to R manual and the posting guides and hope I am not violating
2011 Aug 05
2
R compare cells in one matrix
Good morning! Please, could you help me with the problem? I have a matrix *144x73.* An example of a matrix: [,1] [,2] [,3] [,4] [,5] [1,] 277.4 276.24 275.62 276.55 278.05 [2,] 277.4 276.24 275.55 276.42 277.72 [3,] 277.4 276.24 275.50 276.22 277.39 [4,] 277.4 276.24 275.42 276.02 277.02 [5,] 277.4 276.22 275.37 275.82 276.64 And I want to *compare*its cells
2011 Jun 22
1
question about read.columns
HI, Dear R community, I have a large data set names dd.txt, the columns are: there are 2402 variables. a1, b1, ..z1, a11, b11, ...z11, a111, b111, ..z111.. IF I dont know the relative position of the columns, but I know I need the following variables: var<-c(a1, c1,a11,b11,f111) Can I use read.columns to read the data into R? I have tried the following codes, but it does not work