# Creating Random Coordinates Inside a Fixed Points

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Hjodie on 27 Sep 2019
Commented: Hjodie on 27 Sep 2019
Im asking for a random number generator inside an area like this;
Size of the rectange is 12 lengt 8 side,
for the circle the radius 2.
From that on I'm planning to create a mash area for my problem's further calculations.
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Fabio Freschi on 27 Sep 2019
If you need to create a mesh outside the PDE environment you may have a look at

Fabio Freschi on 27 Sep 2019
% geometry data
xMax = 12;
yMax = 8;
rCircle = 2;
% number of points
N = 1000;
% points iside the rectangle
P = bsxfun(@times,rand(N,2),[xMax yMax]);
% initial plot of all points
figure, hold on, axis equal
plot(P(:,1),P(:,2),'*');
% translate in the origin
Q = bsxfun(@minus,P,[xMax/2 yMax/2]);
% index of points outside the circle
idx = sqrt(sum(Q.^2,2)) > rCircle;
% keep points outside the circle
P = P(idx,:);
% plot points outside the circle
plot(P(:,1),P(:,2),'o');
Hjodie on 27 Sep 2019
Appreciated, thanks for the help which is that fast :)