Re: to test whether line-segments cross - what am I doing wrong?

[Karim Belabas <Karim.Belabas@math.u-bordeaux1.fr>]

* john n [2007-06-20 00:48]:
> 
> Newbie question... I'm trying to write a routine to test for whether two
> unit-length line-segments cross.
> 
> I'm OK with the maths, but am having problems implementing it!
> All I need to do is store either 0 or 1 in the variable 'cross', according
> to whether the line-segments cross or do not cross.
> 
> But I keep getting "%1 = cross-1", and then when I run it again with the
> same input, I get "%2 = 31".
> There's surely a simple reason for this, obvious to any non-newbie, but I
> haven't worked out what it is!

Just rename cross-test ---> cross_test

[ - is the 'minus' operator ]

Cheers,

    K.B.
--
Karim Belabas                  Tel: (+33) (0)5 40 00 26 17
Universite Bordeaux 1          Fax: (+33) (0)5 40 00 69 50
351, cours de la Liberation    http://www.math.u-bordeaux.fr/~belabas/
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