Graphing Inequalities from student input

I am trying to graph a student input such as x>4 or x≥4 on a number line. The graph needs to include the appropriate open or closed endpoint. Here is what I have so far: Slide 9

Check out my modification to screen 11. [Copy of] 7-6.13 Reintroducing Inequalities • Activity Builder by Desmos
I was able to use regressions to find the endpoints of the interval and then conditionally display the points. It won’t work for unions of intervals (which can usually be made by just placing commas between inequalities). It also won’t handle irrational numbers because of the way the regression rounds. I’m hoping it will still work.

If you could guarantee that the students would only enter integers, then there might be the option to solve the problem using lists that checked against conditions, but I don’t know whether you need to deal with non-integer endpoints.

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Wow! Thanks. Surprising to me how hard it is to get Desmos to do this.

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