Question

How to measure the length of the circle and compare them​

Answer 1

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To achieve this, a common measure of circularity is given by four times pi times the area divided by the perimeter squared: C = 4_pi_A/P^2 ~ 12.57_A/P^2, where C is the circularity, A is the area and P is the perimeter. For a circle, C = 1.❤