rand_angle

Below is a demonstration of the features of the rand_angle function

Contents

clear; close all; clc;

Syntax

a=rand_angle(siz);

Description

This function generates a matrix or array of uniformly distributed random angles (of the size siz) in the range [0 2*pi]. The function operates by first creating angles in the range 0-pi/2. The angles are next converted to unit vectors in the unit circle. The X and Y components of these vectors are next independantly and randomly negated. This negating or flipping operation causes the vectors to uniformly but randomly span the entire cirle. Nexts the vectors are converted to an angle in the range [0 2*pi].

Plot settings for examples

markerSize=25;
lineWidth=3;
fontSize=35;

Examples

siz=[500,1]; %Size of desired output
a=rand_angle(siz); % The random angles

cFigure; hold on;
xlabel('Angles'); ylabel('Count');
histogram(a,linspace(0,2*pi,6));
set(gca,'FontSize',fontSize);
drawnow;

Visualization

%Create circle coordinates to visualize circle curve
t=linspace(0,2*pi,100)';
vc=[cos(t) sin(t)];
N=[cos(a) sin(a)];

cFigure; hold on;
hp1=plotV(vc,'b-','LineWidth',lineWidth);
hp2=plotV(N,'k.','MarkerSize',markerSize);
axis tight; axis equal; box on; grid on;
view(2);
set(gca,'FontSize',fontSize);
legend([hp1 hp2],{'Circle boundary','Uniformly distributed points on circle'},'Location','NorthOutside');
drawnow;

GIBBON www.gibboncode.org

Kevin Mattheus Moerman, [email protected]

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License: https://github.com/gibbonCode/GIBBON/blob/master/LICENSE

GIBBON: The Geometry and Image-based Bioengineering add-On. A toolbox for image segmentation, image-based modeling, meshing, and finite element analysis.

Copyright (C) 2006-2021 Kevin Mattheus Moerman and the GIBBON contributors

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Published with MATLAB® R2021a