Polar Area applet - works MOST of the time. Why not all?

crollinson shared this question 1 week ago
Answered

I've been working on this applet. It seems to work most of the time but sometimes crashes. Looking at the lists, sometimes they all collapse and become undefined. Why? I think I've well defined the different constructions making up the lists. Any insights would be much appreciated.

I've attached the file. Here is the applet: https://www.geogebra.org/m/zv8mrzjx

Thanks, Chip

Comments (4)

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Please can you provide precise instructions on how to make the lists collapse?

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It's not always consistent. Right now on the applet, simply slide "a" bigger.

Sometimes it behaves, and sometimes it doesn't.

In any case, if you slide "a" or "n" a bit, at some point the lists collapse. I can't figure out the cause since everything seems clearly defined.

Thanks,

Chip

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If you make list l6 visible I think that will give a clue. When a=5.89 the two sets of circles are the same and one of the circles becomes x^2+y^2=0

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Thank you Michael!

The issue was a circle becoming x^2+y^2=0... it therefore had trouble picked two points on that circle! To fix it, I redefined the radii to be 0.0001 if the radius distance origin to the point on the the polar function was less than 0.0001. It now seems to work fun (or at least I could not break it as easily).


I've attached the corrected file. Here's the corrected applet: https://www.geogebra.org/m/zv8mrzjx

Thanks again!

Chip

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