diff toolboxes/FullBNT-1.0.7/KPMtools/draw_ellipse_axes.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
parents
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/KPMtools/draw_ellipse_axes.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,19 @@
+function h = draw_ellipse_axes(x, c, linespec)
+% DRAW_ELLIPSE_AXES(x, c, linespec)
+%   Draws the major and minor axes of ellipses.
+%   Ellipses are centered at x with covariance matrix c.
+%   x is a matrix of columns.  c is a positive definite matrix.
+%   linespec is optional.
+
+[v,e] = eig(c);
+v = v*sqrt(e);
+
+h = [];
+for j = 1:cols(v)
+  x1 = repmat(x(1,:),2,1) + repmat([-1;1]*v(1,j),1,cols(x));
+  x2 = repmat(x(2,:),2,1) + repmat([-1;1]*v(2,j),1,cols(x));
+  h = [h line(x1,x2)];
+end
+if nargin > 2
+  set_linespec(h,linespec);
+end