# How do I change the orientation of a marker randomly?

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vishakha vijaykumar on 12 Apr 2017
Answered: Thorsten on 12 Apr 2017
I have created 2 random points represented by the '+' marker. I want to change the orientations of these 2 markers randomly. Can anyone help me out? This is my code so far
x=rand(1,2)*100;
y=rand(1,2)*100;
scatter(x,y,'+');
I want random orientations of the 2 '+' markers.
vishakha vijaykumar on 12 Apr 2017
Yup the marker orientation. I apologize for the mistake . I will rephrase my question. Thank you.

Roger Stafford on 12 Apr 2017
If you mean random orientation with respect to the cartesian coordinate origin, and if the orientation change is to be the same for each point, then do this:
t = 2*pi*rand-pi;
x2 = x*cos(t)-y*sin(t);
y2 = x*sin(t)+y*cos(t);

Thorsten on 12 Apr 2017
You have to draw two crossing lines of a random angle. You cannot change the orientation of Matlab's markers.
The following function may be useful; you have to adjust the size of marker using r depending on your axis, and use
axis equal
To get a random angle, set alpha to rand*2*pi.
function plotcrossmarker(alpha, r, x0, y0)
if nargin < 1, alpha = 0; end;
if nargin < 2, r = 1; end
if nargin < 3, x0 = 0; end
if nargin < 4, y0 = 0; end
x = r*cos(alpha);
y = r*sin(alpha);
xx = [-x x NaN -y y];
yy = [-y y NaN x -x];
line(xx + x0, yy + y0)