# How to find where a circle lie between which range?

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Abdel-Rahman Eltaib on 28 Dec 2021 Ive a probelem where I need to caclculate the score of the bullet holes or makings. I was able to find the bullet holes or small circles, and was also able to detect the ranges or big circles. I just to make a loop that will detect where these small circles lie between which range.
Sargondjani on 28 Dec 2021
I mean, if you can find each bullet hole, then you already have some kind of loop? So I don't understand why you can identify the position of each circle.
Maybe provide a minimum working example (or short version of your code).

Adam Danz on 28 Dec 2021
1. Convert the (x,y) coordinates of the 5 holes to polar coordinates using [theta,rho]=cart2pol(x,y)
2. The rho values are the radial distances from the hole coordinates to the center of the target. Compare those results against the eccentricities of the rings to determine which ring each hole belongs to.
Demo
Create target and holes
cla
hold on
theta = linspace(0,2*pi);
plot(r*sin(theta), r*cos(theta), 'r-')
end
axis equal
rng('default') % for reproducibility
[xHole, yHole] = pol2cart(2*pi*rand(1,5), 10*rand(1,5));
plot(xHole, yHole, 'k*', 'MarkerSize', 10, 'LineWidth', 1)
% Label bands
Given coordinates of holes (xHole, yHole) and the radii of target bands (radii), identify the band that contains each hole.
% Measure distance to center
radiiInf = [radii, inf]; % to account for holes outside of outer ring
% Identify band for each hole
% Show results in table
T = table(xHole(:), yHole(:), holeRad(:), holeBand(:), ...
'VariableNames', {'x','y','Distance','Band'})
T = 5×4 table
x y Distance Band _______ ________ ________ ____ 0.38582 -0.89585 0.9754 1 2.3112 -1.5539 2.785 3 3.8185 3.915 5.4688 6 8.1915 -4.958 9.5751 10 -6.5001 -7.1309 9.6489 10
% Label the band for each hole
text(xHole+.5, yHole, compose('%g', holeBand), 'Color', 'b') R2021b

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