How to use VectorAnalysis package?
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg225] How to use VectorAnalysis package?
- From: Richard Q. Chen <chen at fractal.eng.yale.edu>
- Date: Wed, 23 Nov 94 14:11:19 EST
Hi,
I have some problems using the vector analysis package.
The following shows a typical session:
Mathematica 2.2 for Solaris
Copyright 1988-93 Wolfram Research, Inc.
-- Open Look graphics initialized --
In[1]:= Needs["Calculus`VectorAnalysis`"]
In[2]:= SetCoordinates[Cylindrical[]]
Out[2]= Cylindrical[r, theta, z]
In[3]:= a={a1,a2,a3}
Out[3]= {a1, a2, a3}
In[4]:= n={0,0,1}
Out[4]= {0, 0, 1}
In[5]:= CrossProduct[a,n]
2 2 2 2
Out[5]= {Sqrt[a1 Cos[a2] + a1 Sin[a2] ],
> ArcTan[a1 Sin[a2], -(a1 Cos[a2])], 0}
Since I already set cooridinate to be cylindrical, I suppose
a={a1,a2,a3} means that a1 is the r-component, a2 theta-
component and a3 z-component. But Mma seems not doing this.
What I want is that CrossProduct[a,n] gives {a2,-a1,0}
How to do this?
Thanks for any info.
Richard