Thank you. hadley wickham <[email protected]> napsal dne 07.09.2009 15:50:03:
> On Mon, Sep 7, 2009 at 8:36 AM, Petr PIKAL<[email protected]> wrote: > > Dear all > > > > Colleague of mine ask me if R is capable of Andrews plot like > > andrewsplot(x) in Matlab. > > > > Quick search did not reveal anything but before I start to write any > > routine I would like to ask this ingenious audience if there is any > > implementation of Andrews plots somewhere. > > Here's the code I use in the tourr package: > > #' Compute Andrews' curves > #' > #' This function takes a numeric vector of input, and returns a function which > #' allows you to compute the value of the Andrew's curve at every point along > #' its path from -pi to pi. > #' > #' @param x input a new parameter > #' @return a function with single argument, theta > #' > #' @examples > #' a <- andrews(1:2) > #' a(0) > #' a(-pi) > #' grid <- seq(-pi, pi, length = 50) > #' a(grid) > #' > #' plot(grid, andrews(1:2)(grid), type = "l") > #' plot(grid, andrews(runif(5))(grid), type = "l") > andrews <- function(x) { > n <- length(x) > y <- rep(x[1] / sqrt(2), length(t)) > > function(t) { > for(i in seq(2, n, by = 1)) { > val <- i %/% 2 * t > y <- y + x[i] * (if(i %% 2 == 0) sin(val) else cos(val)) > } > y / n > } > } > > > > I know about parallel coordinate plots in lattice (although I do not use > > them as I am not sure what the plot tells me :-). > > If you don't understand parallel coordinates plots, I think you're > going to find Andrew's curves even harder to understand. As I said, the question was from my colleague. Maybe he knows what to expect from such plots. I just told him that I did not find any direct implementation but that it seems to me rather straightforward to make such a plot if I knew what shall be on x axis and on y axis. Regards Petr > > Hadley > > > -- > http://had.co.nz/ ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
