Re: Wrong behavior of CrossProduct

*To*: mathgroup at smc.vnet.net*Subject*: [mg7997] Re: Wrong behavior of CrossProduct*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Wed, 30 Jul 1997 23:57:50 -0400*Organization*: University of Western Australia*Sender*: owner-wri-mathgroup at wolfram.com

Sergio Rojas wrote: > After playing a little bit with the Mathematica construction for the cross > product of two vectors, implemented by the function CrossProduct of the > package VectorAnalysis, I strongly believe that CrossProduct do not > work properly on Mathematica ... *) ... > In[1]:= Needs["Calculus`VectorAnalysis`"]; > In[2]:= SetCoordinates[Spherical[r,theta,phi]]; > In[3]:= V = {a1,a2,0}; > In[4]:= U = {0, 0, 1}; > In[5]:= CrossProduct[U,V] > Out[5]= {0, 0, 0} > (* Again, wrong result. Same results were obtained on *) Why do you say this result is wrong? Your vector U={0, 0, 1}=={r,theta,phi} has zero length. Cheers, Paul ____________________________________________________________________ Paul Abbott Phone: +61-8-9380-2734 Department of Physics Fax: +61-8-9380-1014 The University of Western Australia Nedlands WA 6907 mailto:paul at physics.uwa.edu.au AUSTRALIA http://www.pd.uwa.edu.au/Paul God IS a weakly left-handed dice player ____________________________________________________________________