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Function arma is crashing in some (pathological, but crashing is never good) cases. For example: library(tseries) arma(c(2.01, 2.22, 2.09, 2.17, 2.42), order=c(1,0)) I came to that pathological series while...

Why is this an error? mat <- matrix(1:64, 8, 8) x <- y <- 1:8 z <- outer(x, y, function(x, y) mat[x,y]) when this is not an error: mat <- matrix(1:64, 8, 8) x <- y <- 1...

I mean, I can generate a expression, for example, with: z <- expression(x+y) But then how can I _use_ it? Is it possible to retrieve information from it, for example, that z is a sum, its first argument is...

What is the inverse of encodeString? For example, \u1 is some Unicode symbol. If I do s <- encodeString("\u1") then s will be the string "\001". But anything I do with s, will not return the Unicode that corresponds to...

Is there any way to write an imagematrix generated by the rimage package? Reproducible example: library(rimage) x <- read.jpeg(system.file("data", "cat.jpg", package="rimage")) png("newcat.png") plot(x) dev.off() The newcat.png image is different...

I wrote: > > library(XML) > tt <- xmlHashTree() > head <- addNode(xmlNode("head"), character(), tt) > test <- addNode(xmlNode("test", attrs=c(pi="4")), head, tt) > tt # ok > saveXML(tt, file="test.xml") # error > I found a way to circumvent this error, by replacing...

[I tried to send this messages two days ago, but I guess I mistyped the To: address...] Why "system" is different in Linux and Windows? Both in R 2.4.1, but in Windows there is an option: system(something...

I need arguments pro-S-PLUS and against SAS for a meeting I will have next week. S-Plus is (90 - 99)% compatible with R, so using S-Plus will make things much easier for everyone. But I can't...

This must be dumbest question ever asked, but... When I ask help.search("tcltk"), I get a reference to tcltk-package. When I ask help("tcltk-package"), I get "rtfm(s) in 'R_HOME/Tcl/doc'". But then when I...

This works: grep("([A-Za-z]*) ", "Aaaa 3 x 0 Bbbb") # 1 This also works: grep("([A-Za-z]*) ", "Aaaa 3 x 0 Bbbb", value=T) # Aaaa 3 x 0 Bbbb However, I want a grep that returns the _matched...

I have a time series x = f(t), where t is taken for each month. What is the best function to detect if _x_ has a seasonal variation? If there is such seasonal effect, what is the best function to...

Why does as.numeric convert matrices and arrays to vectors? as.numeric(matrix(c("1", "2", "3", "4"), 2, 2)) [1] 1 2 3 4 I could only figure out ugly ways to bypass this, like: x <- matrix(c("1...

Dylan Arena wrote: > > I'm writing a function that calculates the probability of different > outcomes of dice rolls (e.g., the sum of the highest three rolls of > five six-sided dice). > You know there are simpler ways to do...

Ted Harding wrote: > >> Creating more than one graphic windows is, as far as I know, not >> possible in R. > > But, as to whether/to what extent X or equivalent is available for > MS Windows, that is another question on which...

Oops... Check... http://en.wikipedia.org/wiki/Chi-square_distribution The Chi-square distribution for _any_ df has mean = df and variance = 2df, so for large df, it's approximately a normal distribution with mean = df and sd = sqrt(2...

Gabor Grothendieck wrote: > >>> But then when I ask help.search("R_HOME"), I get nothing. >>> >>> Is something missing here in those help pages? > > Note that R_HOME corresponds to the R.home() path > So I guess there _is_ something missing...

Is there any version of grep that gets information from the filename? For example: x <- "myfile.txt" y <- grep.file("my text", x) should return in y the lines with my text. I know that x <- "myfile.txt" y <- grep...

I want to make a plot, but instead of showing _numerical_ values, I would like to show _symbolic_ values. For example, I want to plot a function y = a x + b, where x varies between Xmin and Xmax. I would...

hadley wickham wrote: > >> intToUtf8(33) # error. Argument x must be an integer vector >> intToUtf8(33:35) # ok >> intToUtf8(40 + 0:9) # error. Argument x must be an integer vector > > Well you need to give it integers! > > intToUtf8(33L) > intToUtf8(40L...

I found a curious bug in read.xls. I don't know if it's reproducible. It's like this: suppose I do a read.xls in a spreadsheet. A column begins with a number. Then, any strings below it...