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citation from wikipedia:

It is possible for two curves to have small Hausdorff distance but large Fréchet distance

Can anybody give me an example where this occurs?

(sub-question: is it even true?)

kahen
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Riko
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1 Answers1

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I have finally found such an example. The weak Fréchet distance is shown on the picture below, the Fréchet distance (not the weak one) is even larger (actually about half the horizontal length of the figure). enter image description here

Source: http://www.diss.fu-berlin.de/diss/servlets/MCRFileNodeServlet/FUDISS_derivate_000000002618/06_weakfrechet.pdf;jsessionid=5D37D207AC877A82292DA83FA48EBD4F?hosts=

Riko
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    The Fréchet distance in this example is actually about half the horizontal length of the figure, because the point on $f$ can only move forwards while the point on $g$ goes back and forth between the left and right extremes. –  Apr 24 '14 at 19:12
  • @Rahul Yes, you are right, I forgot to mention that it is actually the weak Fréchet distance shown on the picture, I will clarify it – Riko Apr 24 '14 at 20:39