# Circle expression

Hello, I have a simple question.

How can I obtain the graph of a circle by using the expression component?
I want to make a circle with midpoint (0,r) and radius r.

x^2+y^2=r^2 is an implicit equation. In order to generate a curve based on a single parameter, you need an explicit equation. For example \{r*Cos(t), r*Sin(t), 0.0\}, where t goes from 0.0 to 2\pi.

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Thank you for your response David.
The explicit equation you give results in an invalid expression (1364). Maybe I’m not entering it correctly?
It works when I split the expression, but then I don’t know whether it’s even possible to convert this into a single coordinate?
When I write the formula for half a circle, the screenshot shows pretty much what I want to achieve.
However, I obtain these ‘NaN’ values (for negative roots I guess), so the curves aren’t connected anymore. Would you know how to keep them connected when lowering the radius of curvature?

If you want to make a circle from a list of points, there’s nothing wrong with the equation in the expression component except that you use parentheses instead of “Curly brackets”

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