ellipse

I would like to make a sector of a circle on WP7. I tried to do this with the ellipse class and I found a lot of solution, which make a gauge or pie chart or something, but I need just the essence. Could anyone help? the aim is to show just one part of a circle (or ellipse). Like the yellow area in the picture: Thanks, Laci Here's a fairly simple solution to the problem, though it does not use an Ellipse and it requires a little trigonometry: <Path Fill="Black" Data="M0,0 L0,-100 A100,100 0 0 1 70.7,-70.7 z" /> The Data property uses Path Markup Syntax . The "M" at the beginning tells the pen

I would like to reproduce the following figure in MATLAB: There are two classes of points with X and Y coordinates. I'd like to surround each class with an ellipse with one parameter of standard deviation, which determine how far the ellipse will go along the axis. The figure was created with another software and I don't exactly understand how it calculates the ellipse. Here is the data I'm using for this figure. The 1st column is class, 2nd - X, 3rd - Y. I can use gscatter to draw the points itself. A = [ 0 0.89287 1.54987 0 0.69933 1.81970 0 0.84022 1.28598 0 0.79523 1.16012 0 0.61266 1

I want to extract the red ball from one picture and get the detected ellipse matrix in picture. Here is my example: I threshold the picture, find the contour of red ball by using findContour() function and use fitEllipse() to fit an ellipse. But what I want is to get coefficient of this ellipse. Because the fitEllipse() return a rotation rectangle (RotatedRect), so I need to re-write this function. One Ellipse can be expressed as Ax^2 + By^2 + Cxy + Dx + Ey + F = 0; So I want to get u=(A,B,C,D,E,F) or u=(A,B,C,D,E) if F is 1 (to construct an ellipse matrix). I read the source code of

How to test if a point P = [xp,yp] is inside/outside some rotated ellipse given by the centre C=[x,y], a, b, and phi ( angle of rotation)? At this moment I am using the following solution: rotate ellipse and point by the angle -phi and then the common test for a position of the point and "non rotated" ellipse. But there are a lot of tested points (thousands) and I find this solution as slow. Is there any direct and more efficient way to get a position of the rotated ellipse and point? I do not need a code but the algorithm. Thanks for your help. Another option is just to throw everything into

I have an R function which produces 95% confidence ellipses for scatterplots. The output looks like this, having a default of 50 points for each ellipse (50 rows): [,1] [,2] [1,] 0.097733810 0.044957994 [2,] 0.084433494 0.050337990 [3,] 0.069746783 0.054891438 I would like to superimpose a number of such ellipses for each level of a factor called 'site' on a ggplot2 scatterplot, produced from this command: > plat1 <- ggplot(mapping=aes(shape=site, size=geom), shape=factor(site)); plat1 + geom_point(aes(x=PC1.1,y=PC2.1)) This is run on a dataset, called dflat which looks like this: site geom