dot & cross binding powers + softbox workaround?
- Subject: dot & cross binding powers + softbox workaround?
- From: Stavros Macrakis
- Date: Fri, 24 Aug 2012 09:06:27 -0400
Haven't looked at the code, but I wonder if the ~/. simplification code
thinks that constantp implies scalarp?
On Fri, Aug 24, 2012 at 7:56 AM, Barton Willis <willisb at unk.edu> wrote:
>
> (%i1) (load(vect), load("soft_box.mac"))$
>
> (%i2) R : matrix([-1,0,0],[0,1,0],[0,0,1])$
> (%i3) e : ([1,2,3] ~ [4,5,6]) . R;
>
> (%o3) [1,2,3] . [4,5,6]~matrix([-1,0,0],[0,1,0],[0,0,1])
>
> Opps--this is bogus--Maxima ignores the parens?
>
> (%i4) args(e);
> (%o4) [[1,2,3],[4,5,6]~matrix([-1,0,0],[0,1,0],[0,0,1])]
>
> (%i5) express(e);
> ~ used with improper arguments:
> [4,5,6]matrix([-1,0,0],[0,1,0],[0,0,1])
>
> A workaround using softbox:
>
> (%i6) softbox([1,2,3] ~ [4,5,6]) . R;
> (%o6) ([1,2,3]~[4,5,6]) . matrix([-1,0,0],[0,1,0],[0,0,1])
>
> (%i7) express(%);
> (%o7) matrix([3,6,-3])
>
> --Barton
>
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