intersection and index of intersection point

alextrocado shared this problem 5 years ago

Solved

i'm trying to intersect a 4th degree implicit curve with a sequence of vertical lines to obtain the intersection points with every branch.

Using the intersection command with the index of intersection doesn't give us all points.

Anyone can help?

The same problem

Comments (5)

Simona Riva ● 5 years ago

Please post your file.

I've tried right now with a classic curve and a family of lines defined by a slider (to avoid huge, continuous computation), and it seems to be working.

Files: Forum.ggb

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alextrocado ● 5 years ago

My file with 3 situations that fail...

Files: error.ggb

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mathmagic ● 5 years ago

I think sometimes intersect(object,object,index) does not work when the amount of points is variable

try {intersect(a,g)}

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Zbynek ● 5 years ago

Problem is that

Sequence(Intersect(a, Element(L_1, i), 2), i, 1, 9)

gets rewritten as

Sequence(Intersect(a, -(x(Element(L_1, i)) / y(Element(L_1, i))) x - z(Element(L_1, i)) / y(Element(L_1, i)), 2), i, 1, 9)

The problem was fixed for the next release but given that this happens on saving you will need to recreate the file once 5.0.466.0 / 6.0.466.0 is available.

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Michael Borcherds ● 5 years ago

v466 online now

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