Re: Dimensions and Variables
- To: mathgroup at smc.vnet.net
- Subject: [mg13728] Re: Dimensions and Variables
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Wed, 19 Aug 1998 01:38:20 -0400
- Organization: University of Western Australia
- References: <6r102b$fi7@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Naum Phleger wrote:
> 1)Why does Dimensions comand return 2 for x*Cos[y]? I need to check
> dimensions of quantities and this makes it dificult to do.
The Dimensions function in Mathematica yields the structure of
expressions, e.g., for a matrix,
In[1]:= Dimensions[{{a, b}, {c, d}}] Out[1]= {2, 2}
You may find that the Miscellaneous`Units` package (which comes with
Mathematica) is relevant to what you are after.
> 3)Does Mathematica Know anything about map projections. I have a vector
> feild of the sky and I want to plot it in a certin projection. All I
> have been able to do so far is plot vectors on square euclidian space.
Have a look at Miscellaneous`WorldPlot` (and also Graphics`ComplexMap`).
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.physics.uwa.edu.au/~paul
God IS a weakly left-handed dice player
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