search for: oliveirahorta

Hello there, any ideas on how to save all the objects on my workspace inside a list object? For example, say my workspace is as follows ls() [1] "x" "y" "z" and suppose I want to put these objects inside a list object, say object.list <- list() without having to explicitly write down their names as in object.list$x = x object.list$y = y object.list$z = z Is

Hi! I was wondering if there are any other functions for numerical integration, besides 'integrate' from the stats package, but which wouldn't require the integrand to be vectorized. Oh, and must be capable of integrating over (-inf,+inf). Thanks in advance, Eduardo Horta [[alternative HTML version deleted]]

Hello! I have a csv file of intra-day financial data (5-min closing prices) that looks like this: (obs - the dates are formated as day/month/year, as is usual here in Brazil) Date;Time;Close 01/09/2009;10:00;56567 01/09/2009;10:05;56463 01/09/2009;10:10;56370 ##(goes on all day) 01/09/2009;16:45;55771 01/09/2009;16:50;55823 01/09/2009;16:55;55814 ##(jumps to the subsequent day)

Hello, this is probably a recurrent question, but I couldn't find any answers that didn't involve the expression "data frame"... so perhaps I'm looking for something new here. I wanted to find a code equivalent to > x=sqrt(1:10) > y=log(1:10) > plot(1:10, x, type="lines", col="darkgreen") > lines(1:10, y, col="red") to use with

Hello, say I have an object > x = list(first = 10, second = 20, third = "Yeah!") and want to remove the $second element of that list. My first try was, of course, > rm(x$second) which gave me the following error message > Error in rm(x$second) : ... must contain names or character strings Any ideas here, folks? Best regards, and Merry Christmas! Eduardo Horta

Hello, Are there any packages which allow for a good integration between R and LaTex / LyX? I'm interested mainly in automatic (automagic?) imports of plots/graphics. Thanks in advance and best regards, Eduardo de Oliveira Horta [[alternative HTML version deleted]]

Hello there I have a list, Y, and each component of that list is a real-valued function (that is, Y[[i]](u) returns a number). I was wishing to build the mean function and the first thing I thought of was Ybar<-function(u){ mean(Y[[1:n]](u)) } but obviously this doesn't work, since Y[[1:n]] is not allowed at all. Any elegant suggestions? I really would like to avoid something like

Hello, I'm willing to plot a sequence of densities on a 3d graph, something like ----------------------------------------------------------------- x <- sapply(1:10, function(i)rnorm(1000)) f <- sapply(1:10, function(i)density(x[,i], from=-5,to=5)$y) grid <- density(x[,1], from=-5,to=5)$x win.graph() persp(grid1, 1:10, f,theta=-50, phi=30, d=2)

Hello, I want to save a pdf plot using Cairo, but the canvas of the saved file seems too large when compared to the actual plotted area. Is there a way to control the relation between the canvas size and the size of actual plotting area? Thanks in advance, and best regards, Eduardo Horta [[alternative HTML version deleted]]

Is there a way to achieve lbl=c("a", "b", "c", "d") par(mfrow=c(2,2), ann=FALSE) for (t in 1:4){ plot(seq(from=1,to=2*pi,length=100), sin(t*seq(from=1,to=2*pi,length=100)), type="l") title(main=paste("(", lbl[t], ")", sep="")) } without having to use an object like 'lbl'? More generally: is it possible

Hello there, Straight to the point: it seems that CairoPDF from package "Cairo" cannot handle greek letters from expression(). For example, > eta = seq(from=-pi, to=pi, length=100) > f = sin(eta)^2 > pdf(file = "temp_pdf.pdf") > plot(eta, f, type="l", main=expression(f(eta)==sin(eta)^2), xlab=expression(eta), ylab=expression(f(eta))) > dev.off()

Hello there I wish to get the "coordinates" of the minimum element of an array. For example, if the array were > H = array(c(8:5,1:4),dim=c(2,2,2)) > H , , 1 [,1] [,2] [1,] 8 6 [2,] 7 5 , , 2 [,1] [,2] [1,] 1 3 [2,] 2 4 then > min(H) [1] 1 and > max(H) [1] 8 Say "idx" were the function I'm looking for. Then, what

Hi there, yet on the topic of greek letters and pdf plotting: when I run the following code pdf(file="temp.pdf") mu=seq(from=-pi, to=pi, length=100) plot(mu, sin(mu^2), type="l", xlab=expression(mu%in%(list(-pi,pi))), ylab=expression(sin(mu^2)), main=expression((list(mu,sin(mu^2))))) dev.off() I get a "proportional to" symbol in place of a

Hello, I've googled for a while and couldn't find anything on this topic: say I have a matrix A and want to build matrices B1, B2,... using blocks from A (or equivalently an array B with B[,,i] being a block from A), and that I must sum the B[,,i]'s. I've come up with this rather non-elegant code: > n = 6 > p = 3 > > A <- matrix(1:(n^2), n, n, byrow=TRUE) >

In my last e-mails, I have asked for help regarding 1. 'defining functions inside loops' 2. 'integrating functions / vector arithmetics' 3. 'vectors out of lists?' 4. 'numerical integration' Since some of these topics seemed to be relevant (I'm guessing by the # of replies I got), I'm posting a modified section of my code. Any thoughts on improvements would

Hello, I was trying to build some functions which I would like to integrate over an interval using the function 'integrate' from the 'stats' package. As an example, please consider the function h(u)=sin(pi*u) + sqrt(2)*sin(pi*2*u) + sqrt(3)*sin(pi*3*u) + 2*sin(pi*4*u) Two alternative ways to 'build' this function are as in f and g below: coeff<-sqrt(1:4)

Hello, I was trying to define a set of functions inside a loop, with the loop index working as a parameter for each function. Below I post a simpler example, as to illustrate what I was intending: f<-list() for (i in 1:10){ f[[i]]<-function(t){ f[[i]]<-t^2+i } } rm(i) With that, I was expecting that f[[1]] would be a function defined by t^2+1, f[[2]] by t^2+2 and so on.