similar to: inverse function of order()

I wanted to test if there exists already a name (which is incidentally a substring of another name) in a dataframe. I did e.g.: > data(swiss) > names(swiss) [1] "Fertility" "Agriculture" "Examination" "Education" [5] "Catholic" "Infant.Mortality" > ! is.null(swiss$EduX) [1] FALSE > !

What is the reason, that the levels of the factor returned by cut() are not marked as ordered levels? > is.ordered( cut( breaks=3, sample(10 ) ) ) FALSE > help(factor) ... If 'ordered' is 'TRUE', the factor levels are assumed to be ordered. ... Wolfram

Dear list, how can I compute the inverse of the X'WX matrix ("inverse of the weighted sum of squares and crossproducts matrix") from an object of class "lm" from a weigthed linear regression? Thanks, Sven

Is there a simple possibility to become directly a matrix from a call of sub() on a matrix? --------- START OF LOGFILE ---------------- # R 1.4.1 > a <- matrix( letters[1:6], 2, 3 ) # a is a matrix > print( a ) [,1] [,2] [,3] [1,] "a" "c" "e" [2,] "b" "d" "f" > b <- sub( '(.)', '-\\1-', a )

What is the easiest way to change within vector of strings each letter after a space into a capital letter? E.g.: c( "this is an element of the vector of strings", "second element" ) becomes: c( "This Is An Element Of The Vector Of Strings", "Second Element" ) My reason to try to do this is to get more readable abbreviations. (A suggestion would be to

I propose to add a function that allows to display colors selected by a text pattern or by color vectors in a plot. Wolfram Fischer #--- showcolors.R showcolors <- function( col = "red" , index = NULL , pie = TRUE , lwd = 6 , cex = 1.0 , main = NULL , sub = NULL , ... ){ n.colors <- length( col ) if( n.colors > 1 ){ main <- deparse( substitute( col ) )

I would propose to add " See also: `nchar' for counting the number of character in character vectors. " to the helpfile of length(), because it is rather difficult to find nchar() if one has only search terms as "length", "len", "strlen" in mind. Sincerly Wolfram Fischer

If I use the Ineq library and the Gini function in this way: >Gini(c(100,0,0,0)) I obtain the result 0.75 instead of 1 (that is the perfect inequality). I think Gini's formula in Ineq is based on a formula as reported here: http://mathworld.wolfram.com/GiniCoefficient.html but in the case of perfect inequality: x_1=.......=x_n-1 =0 x_n>0 these formula are equal to 1 - 1/n, not to

Is there a function in R that corresponds to the function ``map'' of perl? It could be called like: vector.a <- map( vector.b, FUN, args.for.FUN ) It should execute for each element ele.b of vector.b: FUN( vector.b, args.for.FUN) It should return a vector (or data.frame) of the results of the calls of FUN. It nearly works using: apply( data.frame( vector.b ), 1, FUN,

Dear All, I have written the following programs to find a non-singular (10*10) covariance matrix. Here is the program: nitems <- 10 x <- array(rnorm(5*nitems,3,3), c(5,nitems)) sigma <- t(x)%*%x inverse <- try(solve(sigma), TRUE) while(inherits(inverse, "try-error")) { x <- array(rnorm(5*nitems,3,3), c(5,nitems)) sigma <- t(x)%*%x inverse <-

I downloaded: http://www.bioconductor.org/data/metaData/hgu95av2_1.7.0.tar.gz described as: Package: hgu95av2 Title: A data package containing annotation data for hgu95av2 Version: 1.7.0 Created: Wed Jan 12 16:57:23 2005 Author: Lin,Chenwei Description: Annotation data file for hgu95av2 assembled using data from public data repositories Maintainer:

x.fun <- function( formula, data ) dotplot( formula, data ) x.grp <- function( formula, groups, data ) dotplot( formula, groups, data ) data( barley ) > x.fun( variety ~ yield | site, data=barley ) # no problem > dotplot( variety ~ yield | site, groups=year, data=barley ) # no problem > x.grp( variety ~ yield | site, groups=year, data=barley ) object "year" not found

If I want to plot different widths of line segments or arrows I have to program loops to plot each line apartly. Is that right? n <- 6 x <- 1:n y <- rnorm(1:n) q <- ( x %% 3 + 1 ) * 2 plot( x, y, cex=q ) for( i in 1:(n-1) ) lines( x[i:(i+1)], y[i:(i+1)], lwd=q[i], col=q[i] ) Would it not be possible to make plotting functions accept vectors of line widths (as they

[R 2.0.0 on Linux] I tried: > df <- data.frame( grp1=factor( c('A' ,'A' ,'A' ,'D', 'D' ) ) , grp2=factor( c('a1','a2','a2','d1','d1') ) ) > df grp1 grp2 val 1 A a1 1 2 A a2 2 3 A a2 4 4 D d1 8 5 D d1 16 I got: > with( df, ave( val, grp1, grp2, FUN=sum ) )

Question: How can a repeat a dataframe n times in the direction of the rows? (Or: How I can rbind a dataframe n times ?) Example Data: x <- data.frame( alpha=letters[1:3], num=1:3 ) n <- 4 Complicated solution: To rbind a dataframe n times I can program a loop: xr <- x for( i in 2:n ) xr <- rbind( xr, n ) Observation: To cbind a dataframe n times I

Dear R helpers: Thanks for the previous reply. I am using Friedman racing test. According the the book "Pratical Nonprametric Statistic" by WJ Conover, after computing the statistics, he suggested to use chi-squared or F distribution to accept or reject null hypothesis. After looking into the source code, I found that R uses chi-sqaured distribution as below: PVAL <-

Do any of the R libraries have an implementation of the Inverse Error Function (Inverse ERF)? ref: http://mathworld.wolfram.com/InverseErf.html http://functions.wolfram.com/GammaBetaErf/InverseErf/ Thanks, Nathan [[alternative HTML version deleted]]

On some errors during the plot of a lattice/grid graphics, there is written a message like "Error using packet 1: missing value where TRUE/FALSE needed" into the concering panel and the next panel is plotted. Which option I could use to stop the execution to have a look at the error by a traceback? Regards - Wolfram

Hello, I'm not sure how to state my question in a technically accurate manner, so I'll use a short example to clarify my problem: Say I have a vector, vec<-c(1,2,3,2) I would like to be able to "reference" the vector by using the string containing the name of the vector - that is, I would like to know of some function which is able to convert the string "vec"

R 1.8.1: ___COMMAND____________________________________________ levelplot( yield ~ year * variety | site, barley ) ___ERROR_MESSAGE______________________________________ Error in Summary.factor(..., na.rm = na.rm) : "min" not meaningful for factors ___COMMENT____________________________________________ levelplot( yield ~ as.numeric(year) * as.numeric(variety) | site,