MATLAB - PI value by Monte-Carlo Method

%******************* PI value by Monte-Carlo Method**********************
%**************************** By Mahesha MG ****************************
clc;
n=input('Number of points: ');
x=rand(n,1);
y=rand(n,1);
figure('color','white');
hold all

axis square;
x1=x-0.5;
y1=y-0.5; %cirle has centre at (0.5,0.5)
r=x1.^2+y1.^2;
m=0;   %Number of points inside circle
for i=1:n
    if r(i)<=0.25
        m=m+1;
        plot(x(i),y(i),'b.');
    else

        plot(x(i),y(i),'r.');
    end
end
m/(0.25*n)

SAMPLE OUTPUT (n = 10,000)

ans =

    3.1468

Published with MATLAB® 7.13