using units in Maxima?



> In his example, done in Mathcad, he includes units with 
> his value assignments and calculations.  It it possible to do such a 
> thing in Maxima?  If so, how?  Thanks.
> 
> -Ron Crummett

Maybe something simple will work for you:

(%i1) l : 6.23 * 'feet$
(%i2) w : 5.89 * 'feet$
(%i3) area = l * w;
(%o3) area=36.694699999999997*feet^2
(%i4) subst(feet = mile / 5280,%);
(%o4) area=1.3162412477043157*10^-6*mile^2

Alternatively, there is a 'units' package (try load(units)).
But I don't know how to use the package or if it works.

Barton