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floating point exception in geane [message #6946] Mon, 16 June 2008 16:44 Go to previous message
Anonymous Poster From: *e18.physik.tu-muenchen.de
Hi,

I found a problem with geane. It is related to the propagation to the point of closest approach:

In the method CbmGeanePro::Track3ToPoint a floating point can be produced in two places (maybe even more, but to me it happened in two cases only):

m3 = 1./e3.Mag();
// e3.Mag()==0

and

xpR[1] = 0.5*(xp32[0]*xp3[0]/xp3[1]+ xp3[1]);
// xp3[1]==0

In the moment I work around this problem by throwing an exception if any of the two conditions happen. But of course this issure should be solved. I believe it happens when the 3 points lie in one line. I bet the behaviour depends on the stepping defined inb the geo file. Maybe that is why Sebastian diodnt see it before.

Anyway this should be dealt with. Since you dont use exception handling, you could use your error flags for this and abort the operation if this happens.

Cheers, Christian
 
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