similar to: plot the implicit function

Hi, does anyone know how to plot 3D parametric surface,e.g ellipsoid: x=a*cos(s)*cos(t), y=b*sin(s)*cos(t), z=sin(t); s in [0,2*pi], t in [-pi,pi]. Vytautas Maniusis, Vilnius University, Lithuania

Hey, Is there any function plotting several "implicit functions" (F(x,y)=0) on the same fig. Is there anyone who has an example code of how to do this? The contour3d function in the misc3d package only work with the functions with three dimensions. Thanks a lot. Many thanks for your help. KnifeBoot [[alternative HTML version deleted]]

Hi, I'm new to R (and math ;) Would somebody please be so kind as to direct me in plotting a 3D sphere? I tried something in the lines of: #### y <- x <- seq(-pi, pi, length=pi*10) f <- function(x,y) { z <- sqrt(pi - x^2 - y^2) #z[is.na(z)] <- 0 z } z <- outer(x, y, f) persp(x, y, z, theta = 120, phi = 30) #### I've also tried: .... make.surface.grid(...) ..

Hi, I draw a surface corresponding to bivariate density of independent variables (rho=0) using persp(). Then I add a contour line (i.e., circle in my case) at a particular density. Below is a minimal example of what I have so far. # Bivariate density dnorm2d <- function(x, y, rho = 0) { xoy = (x^2 - 2 * rho * x * y + y^2)/(2 * (1 - rho^2)) density = exp(-xoy)/(2 * pi * sqrt(1 - rho^2))

Dear, I am trying to plot contours (with filled.contour function) inside UK area, so that no contours are plotted over the sea. I was wondering if anyone can help me with this task and if I can get any suggestions how to do that. Thank you, Irina Irina Foss Environmental Research Institute North Highland College UHI Millennium Institute Castle Street Thurso, Caithness Scotland KW14 7JD United

The following example just "hangs", i.e. the final contour() does not terminate. x <- pi*(0.5+((-13):12))/36 w <- 0.377*cos(2*x)*sqrt(abs(cos(2*x))) v <- c(rep(-1.47,13),rep(1.722,13))*abs(sin(x))^1.5 cr <- outer(w,w)+outer(v,v) s <- sqrt(diag(cr)) cr <- cr/outer(s,s) contour(cr[1:26,26:1],levels=seq(-1,1,0.1),axes=T) --please do not edit the information below--

Hello! I have a question on uniform distribution. I want to plot n, say 20, points, uniformly distributed, in a circle, with radius=0.1 and center,say, (0.4, 0.8) I do not know how~ Thank you for your time. Yours Wolfgang Amadeus [[alternative HTML version deleted]]

Hi, I've used the Mathematica to produce 3D graphics, contour plots of a bivariate normal distribution Now I want make these graphics in R, but i do not know how. I would like to: - Plot a 3D graph for some different variance matrix - Plot the contour plots - Find and try to plot (in the 3d graph ou contour plot) the (1-a)% confidence region based in a chi-square(a) with the degrees of

Hi, I would like to plot a x,y curve described by the equation : Ax^2 + Bx + Cy^2 + Dy + E == 0 (A,B,C,D,E are constants) This sounds like quite the common task but haven't been able to figure out how to do this. Could you please help ? I am new to R so probably missing something basic. Thanks

Hi everyone! Could you please help me with the following assignment? My aim is to write a custom function that draws the plots of functions submitted by the user. The catch is, that we do not know the exact number of functions the user will select to draw. The program is relatively easy with one function, f.e sin: mf<- function(f,range,quality){ x<- seq(range[1],range[2],

I'd like to make some polar plots with R, but I can't seem to find anything designed to help with that. Is there anyway to get a real polar mode, where instead of x and y you have r and theta? How about a way to draw a circle? -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send

Hello, has anybody written a function to plot density ellipses (95%, 99% or anything) in a scatterplot? I found nothing in any package, nor in the list archives. There does seem to be a contributed package "ellipse" for S-Plus (on S-Archive), but it does a lot more than what I would need. Still, if anybody ported it to R, I'd be grateful for a link. I'm a bit afraid to try the

Hi, I seem to be unable to get a mixed legend that has lines *or* polygons (not both). For example: ppi <- seq(0,2*pi,length.out=21)[-21] frame() plot.window(ylim=c(-5,5),xlim=c(-5,5),asp=1) polygon(cos(ppi)*4+rnorm(20,sd=.2),sin(ppi)*4+rnorm(20,sd=.2), col="green",border=FALSE) polygon(cos(ppi)*2+rnorm(20,sd=.1),sin(ppi)*2+rnorm(20,sd=.1), col="blue",border=FALSE)

Dear All, Thanks a lot for the useful help again. I manage to get it done up to a point where I think I just need to apply some smoothing/interpolation to get denser points, to make it nice. Basically, I started from Duncen's script to visualize and make the clipping along a plane at a slice. Then I map my data points' values to a color palette and just plot them as points on this plane.

Good to hear you've made such progress. Just a couple of comments: - You should use points3d() rather than rgl.points(). The latter is a low level function that may have unpleasant side effects, especially mixing it with other *3d() functions like persp3d(). - There are several ways to draw a flat surface to illustrate your data. Which one to use really depends on the form of data.

Is it possible to plot unevenly spaced data with image/contour function? Below is an example of the type uneven data that I'm trying to plot with image/contour functions. For example, I would like to have the x-distance on the x-axis and y-distance on the y-axis and then the temperature values determine the color used. Unfortunately this data was sampled such that it is not evenly

Dear R users -- I think this question was asked before but there was no reply to it. I would appreciate any suggestion any of you might have. I am interested in plotting several "implicit functions" (F(x,y,z)=0) on the same fig. Is there anyone who has an example code of how to do this? Thank you Yihsu

Hi, I need to plot a graph with a fixed circle and with a series of point of different size. Here is a "simplified" example: angle<-pi/180*c(0:360) x<-seq(0,2,by=0.2) y<-seq(0,2,by=0.2) z<-seq(0,1,by=0.1) par(pty="s") plot(-2:2,-2:2,type="n") lines(cos(angle),sin(angle)) points(x,y,cex=z) The size of the points compared to the circle (of radius 1) is

By any chance are there any alternatives to image(...) and filled.contour(...) I used Rseek to search for that very topic, but didn't turn over any leads... http://www.rseek.org/?cx=010923144343702598753%3Aboaz1reyxd4&newwindow=1&q=alternative+to+image+and+filled.contour&sa=Search&cof=FORID%3A11&siteurl=www.rseek.org%252F#1238 I'm sure there are some out there, but

In the following example I would like to have the color transition from Red->yellow->green in the image(...) function, and if possible have the yellow be set to correspond with the mean value (for the below 75). ? I was able to figure something like out when using filled.contour(...), e.g. filled.contour(ak.fan, levels = c(70, 73, 76,?80, 90), color = terrain.colors) (I still