Intersection of curves?

SharkD shared this question 2 years ago
Answered

Are there any plans to add the ability to create intersections of parametric curves? Thanks.

Best Answer
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for circle or ellipse: c conic; A,B points on conic c; arc(c,A,B)

for 0º to 120º i think arc(c,point(c,0.5),point(c,0.5+1/3))

Comments (7)

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it is possible only numericly


Intersect( <Curve 1>, <Curve 2>, <Parameter 1>, <Parameter 2> )

Intersect(Curve(2s, 5s, s,-10, 10), Curve(t, 2t, t, -10, 10)) yields A=(0,0).

https://wiki.geogebra.org/e...

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I am trying, but my attempts always result in "undefined". See Point C in the attached document.

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the numeric calculus is very sensitive to initial values. tetha is a number for degree from 0 to 360. I think the values must be bigger

I tried C = Intersect(circSurfOuter, lattSurfEuler_3, 3, 150) and D = Intersect(circSurfOuter, lattSurfEuler_3, 0, 300) and got points.

I think to use conic is better. ie:

e: Conic(circSurfOuter(0), circSurfOuter(1), circSurfOuter(2), circSurfOuter(3), circSurfOuter(4))

f: Conic(lattSurfEuler_3(0), lattSurfEuler_3(50), lattSurfEuler_3(100), lattSurfEuler_3(150), lattSurfEuler_3(200))

Intersect(e, f)

really I think that to use conic from beginning instead curves is better

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[quote]I tried C = Intersect(circSurfOuter, lattSurfEuler_3, 3, 150) and D = Intersect(circSurfOuter, lattSurfEuler_3, 0, 300) and got points.[/quote]

Does theta need a degrees sign ° after the numbers?

I will have to study up on conics.

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I need to do partial curves, such as just 0° to 120° for theta. Is this possible with conics?

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for circle or ellipse: c conic; A,B points on conic c; arc(c,A,B)

for 0º to 120º i think arc(c,point(c,0.5),point(c,0.5+1/3))

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Very good, thanks!

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