similar to: Mod function?

Displaying 20 results from an estimated 10000 matches similar to: "Mod function?"

2006 Dec 10
4
sample "n" random positions from a matrix
Hi there, I have a binary matrix (dim 100x100) filled with values 0 and 1. I need select a record "n" positions of that matrix when values are 1. How can I do that? Thanks for all, Miltinho Brazil --------------------------------- [[alternative HTML version deleted]]
2005 Jan 12
2
?"=" (Windows) (PR#7504)
?"=", ?"==", ?"!=", ?">=", and ?"<=" sends me to the documentation for ?help on Windows, while returning the correct documentation on Linux. Robert > version _ platform i386-pc-mingw32 arch i386 os mingw32 system i386, mingw32 status major 2 minor
2006 Dec 31
4
Does SQL group by have a heavy duty equivalent in R
I have hundreds of humans who have undergone SNP genotyping at hundreds of loci. Some have even undergone the procedure twice or thrice (kind of an internal control). So obviously I need to find those replications, and confirm that the results are the same. If there is discordance then I need to address it. I tried to use the aggregate function nr.attempts
2009 Oct 13
7
lapply() reccursively
Hi all, I was wondering whether it is possible to use the lapply() function to alter the value of the input, something in the spirit of : a1<-runif(100) a2<-function(i){ a1[i]<-a1[i-1]*a1[i];a1[i] } a3<-lapply(2:100,a2) Something akin to a for() loop, but using the lapply() infrastructure. I haven't been able to get rapply() to do this. The reason is that the "real"
2006 May 12
4
bitwise addition
Hello all again, I want to do bitwise addition in R. I am trying to generate a matrix 0000 0001 0010 .... .... 1111 I know the other ways of generating this matrix but I need to look at bitwise addition. Any suggestions??? thanks a lot Nameeta ------------------------------------------------- This email is intended only for the use of the individual or...{{dropped}}
2010 Jul 07
3
How do I test against a simple null that two regressions coefficients are equal?
Hi there, I run two regressions: y = a1 + b1 * x + e1 y = a2 + b2 * z + e2 I want to test against the null hypothesis: b1 = b2. How do I design the test? I think I can add two equations together and divide both sides by 2: y = 0.5*(a1+a2) + 0.5*b1 * x + 0.5*b2 * z + e3, where e3 = 0.5*(e1 + e2). or just y = a3 + 0.5*b1 * x + 0.5*b2 * z + e3 If I run this new regression, I can test against
2005 Mar 09
3
R-2.0.1 Gentoo g77 problem
Hello, I use Gentoo and I can't get R 2.0.1 to compile. I used the portage system, Gentoo's source package sytem, and after it uncompresses the source to R, it says that I don't have a fortran compiler. It told me to use f77 flag and re-emerge gcc, which I did with the f77 and fortran flags, but it still won't compile. Does anyone have any ideas? I suspect that gcc has changed
2006 Dec 14
5
persistant: Matlab->R
Dear list members, Could anyone tell me if there is an equivalent of the Matlab declaration 'persistant' in R? Thank you very much, Bernard Gregorry. (Matlaber converted to R). --------------------------------- [[alternative HTML version deleted]]
2008 May 27
4
help with simple function
I have a matrix of frequency counts from 0-160. x<-as.matrix(c(0,1,0,0,1,0,0,0,1,0,0,0,0,1)) I would like to apply a function creating a new column (x[,2])containing values equal to: a) log(x[m,1]) if x[m,1] > 0; and b) for all x[m,1]= 0, log(next x[m,1] > 0 / count of preceding zero values +1) for example, x[1,2] should equal log(x[2,1]/2) = log(1/2) = -0.6931472 whereas x[3,2] should
2008 Dec 11
3
check if a certain ... argument has been passed on to my user-defined function
Hi, How can I check if a certain ... argument has been passed on to my user-defined function or not? foo <- function(data, ...) { ### here I want to check whether xlab was passed with the ... arguments ### or if the ... arguments did not contain an xlab argument } I tried missing(xlab) , exists(xlab) and several other things but did not find a solution. TIA, Mark
2008 Jan 23
4
image question
Hi, I have a question regarding the image function. Is there a way to specify a separate color set for each column in the matrix? TIA, ajar. [[alternative HTML version deleted]]
2007 Aug 04
2
Mixture of Normals with Large Data
All: I am trying to fit a mixture of 2 normals with > 110 million observations. I am running R 2.5.1 on a box with 1gb RAM running 32-bit windows and I continue to run out of memory. Does anyone have any suggestions. Thanks so much, Tim [[alternative HTML version deleted]]
2008 Dec 09
2
Better way to find distances between points in a set?
I was playing around a bit to see how I could find the two points in a set of points (or ordered pairs) furthest from each other. Here's what I did: 1) created a Nrow by 2col matrix, so each row contains an x,y coordinate pair. 2) fed the matrix to a nested mapply (cv is my matrix): mapply(function(k,l) mapply(function(x,y,a,b) +
2007 Feb 22
4
Crosstabbing multiple response data
Using R version 2.4.1 (2006-12-18) on Windows, I have a dataset which resembles this: id att1 att2 att3 1 1 1 0 2 1 0 0 3 0 1 1 4 1 1 1 ratings <- data.frame(id = c(1,2,3,4), att1 = c(1,1,0,1), att2 = c(1,0,0,1), att3 = c(0,1,1,1)) I would like to get a cross tab of counts of co-ocurrence, which might resemble this:
2009 Nov 16
3
Cluster analysis: hclust manipulation possible?
I am doing cluster analysis [hclust(Dist, method="average")] on data that potentially contains redundant objects. As expected, the inclusion of redundant objects affects the clustering result, i.e., the data a1, = a2, = a3, b, c, d, e1, = e2 is likely to cluster differently from the same data without the redundancy, i.e., a1, b, c, d, e1. This is apparent when the outcome is visualized
2011 Jan 24
2
Help with expression
I have a problem with expressions. I am trying to create a title where the parameter of interest is displayed as a Greek character. Which parameter is being considered is stored in a character variable. As an example, if I have param <- "alpha" and then do plot(0, 0, main = bquote(Parameter==.(param))) then in the title I get "Parameter = alpha", whereas I want the
2009 Feb 16
2
Using eval in multinom argument
Hi, I am having difficulty entering a 'programmable' argument into the multinom function from the nnet package. Interactively, I can get the function to work fine by calling it this way: z1=multinom(formula = class.ind(grp[-outgroup])~ (PC1 + PC2 + PC3), data=data.frame(scores)) However I need to be able to change the number of variables I am looking for in 'scores' and so am
2008 Oct 30
3
why does sample(x, n) give the same n items in every separate runs?
Hello R users, I have gene expression data of two groups of genes (large and small). Gene expression intensities of those genes are classified into 1 to 10 levels. What I want is to make a random set of genes that have the same levels as the small group from large group using sample(). I used smallvec to hold the number of genes in each levels (1 to 10) for small group, largevec for large group.
2006 Dec 12
1
Calculating AICc using conditional logistic regression
I have a case-control study that I'm analysing using the conditional logistic regression function clogit from the survival package. I would like to calculate the AICc of the models I fit using clogit. I have a variety of scripts that can calculate AICc for models with a logLik method, but clogit does not appear to use this method. Is there a way I can calculate AICc from clogit in R? Many
2006 Oct 03
1
latex expression
Dear All: I try to use latex expression in legend, but I am not very clear on the detail rules in R. I remeber there is a R help page list all rules and many examples, but I forget what should I type (?xxx) to get this help page. Could you please remind me which function should I type? Thanks _________________________________________________________________ Find a local pizza place, music