Question

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How can I make Turtle recognize a circle?

I have a function that draws a few circles and I am going to place dots inside them. Depending if the dot falls within the circle, depends on wether the colour will change or not.

The biggest issue I am finding is how to check whether or not the dot is within the circle. Does anyone have any idea how to calculate coordinates within a circle or is their a method which can check coordinates against the circle?

Answer 1

1. Compute (Euclidean) distance to the circle’s center,

   sqrt((x - center_x) ** 2 + (y - center_y) ** 2)
   

2. Check whether the result is less than the radius.