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Re: Ellipe drawing
Posted:
Jun 21, 2013 5:35 PM


On Friday, June 21, 2013 10:16:09 PM UTC+12, aalcaineo wrote: > Hello all > > > > I'm trying to draw an ellipse in the same fashion I did it for a circle, I let you an example > > > > [X,Y] = meshgrid(0:1/SpatSamp:Xmax,0:1/SpatSamp:Ymax); > > Act = sqrt((XLoc(1)).^2+(YLoc(2)).^2); > > > > where SpatSamp is the spatial sampling, Xmax and Ymax are the limits y Loc is a vector with the X,Y coordinates of the center. > > > > the objective is to plot it using "contour" > > > > Any ideas? thank you in advance for your help!
That's a weird way of plotting an ellipse.
Here's an alternative for an ellipse with major axis qmax and minor axis qmin, centre at x0,y0, and orientated theta deg from N. function [x,y]=ellipse(qmax,qmin,theta,x0,y0,n) % % Set up parameters % theta=theta*pi/180; % Orientation from N wt=0:n; % n is no of points 180 is good dwt=2*pi/n; wt=wt'*dwt; sth=sin(theta); cth=cos(theta); % % Calculate ellipse with zero orientation % x1=qmax*cos(wt); y1=qmin*sin(wt); % % Orientate theta deg from north % x=x1*sthy1*cth+x0; y=x1*cth+y1*sth+y0;
plot(x,y)



