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Hi,<br>
<br>
I would like to reask the same question as an old mail sent to this
mailing list last summer (see below). Apparently, it didn't receive any
answer. I notice that m_DT is linked to curvature-based evolution terms
and m_WaveDT to the other evolution terms. Is it because
curvature-based terms is more sensitive to numerical instabilities than
the others and could need a smaller dt?<br>
<br>
How did you choose the following values for m_WaveDT and m_DT? Is
there another justification than the one given by Sethian?<br>
template< class TImageType ><br>
double LevelSetFunction<TImageType>::m_WaveDT = 1.0/(2.0 *
ImageDimension);<br>
<br>
template < class TImageType ><br>
double LevelSetFunction<TImageType>::m_DT = 1.0/(2.0 *
ImageDimension);<br>
<br>
Thanks in advance for your help,<br>
<br>
Valerie<br>
<br>
<pre>"
<i>Sat Aug 6 13:15:37 EDT 2005</i>
Can someone explain why the time step is computed the way it is in
the function ComputeGlobalTimeStep in itkLevelSetFunction.txx?
I mean the mathematical justification. What are m_WaveDT and m_DT?
In Level Set Methods, Sethian only mentions (page 67, section 6.4.1)
max F \Delta T <= \Delta x
A pointer to the appropriate theory would suffice.
Thank you!
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