On 04/03/2013 06:25 PM, thomas wrote:
>
> In doc/src/modules/ga/ga.rst:
>
> > +     \begin{equation*}
> > +        \f{X}{\theta,\phi} = \f{\cos}{\theta}\bm{e_{z}}+\f{\cos}{\theta}\paren{\f{\cos}{\phi}\bm{e_{x}}+\f{\sin}{\phi}\bm{e_{y}}}
> > +     \end{equation*}
> > +
> > +The module *manifold.py* is transitionary in that all calculation are performed in the embedding vector space (geometric algebra).
> > +Thus due to the limitations on *sympy*'s *simplify()* and  *trigsimp()*, simple expressions may appear to be very complicated since they are expressed
> > +in terms of the basis vectors (bases/blades) of the embedding space and not in terms of the vector space (geometric algebra) formed
> > +from the manifold's basis vectors.  A future implementation of *Manifold.py* will correct this difficiency. The member functions of
> > +the vector manifold follow.
> > +
> > +.. function:: Manifold(x,coords,debug=False,I=None)
> > +
> > +   Initializer for vector manifold where *x* is the vector function of the *coords* that defines the manifold and *coords* is the list/tuple
> > +   of sympy symbols that are the coordinates.  The basis vectors of the manifold as a fuction of the coordinates are returned as a tuple. *I*
> > +   is the pseudo scalar for the manifold.  The default is for the initializer to calculate *I*, however for complicated *x* functions (especially
> > +   where trigonometric functions of the coordinates are involved) it is sometimes a g
>
> Is there a reason why this has to be in global namespace instead of, 
> e.g., in the main() function ?
>
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>
I don't understand your comment.  Please explain more fully.