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Rather obscure division by zero in triangleFuncsintersectAxesBundle

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Old   August 12, 2008, 07:42
Default Version: OF-1.5 Description
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Bernhard Gschaider
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Version: OF-1.5

Description: While reading in a STL into snappyHex it crashes with a division by zero in line 142 of meshTools/triSurface/triangleFuncs/triangleFuncs.C

The cause seems to be these parameters for intersectAxesBundle
V0-31.71428 0 -15.10714) V10-1.285715 8.99165e-16 -1.142858) V200 0 -1.678573) i0:0

For these parameters the local variable det = 8.9e-16*1.67 > SMALL (not by much ;) ) but u1=8.99e-16<SMALL and the routine then tries to divide by u2=0

I know it is a one in a million chance that this might happen, but it happened. I propose the following patch that tightens the restriction on det (and fixes this):

triangleFuncs.patch

Bernhard
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Old   August 12, 2008, 18:01
Default Thanks - I put it in. Does the
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Mattijs Janssens
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Thanks - I put it in. Does the mag(u1)<SMALL need some non-dimensionalisation as well?
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Old   August 13, 2008, 07:08
Default It might be good for consisten
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Bernhard Gschaider
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It might be good for consistency but is in my experience not necessary.

Bernhard
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