Re: Multiplying a vector over multiple vectors
- To: mathgroup at smc.vnet.net
- Subject: [mg91179] Re: [mg91150] Multiplying a vector over multiple vectors
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Fri, 8 Aug 2008 07:16:23 -0400 (EDT)
- Organization: Mathematics & Statistics, Univ. of Mass./Amherst
- References: <200808070842.EAA02140@smc.vnet.net>
- Reply-to: murray at math.umass.edu
First /@ Outer[Times, {{1, 2}, {3, 4}, {5, 6}}, {{a, b}}, 1]
{{a,2 b},{3 a,4 b},{5 a,6 b}}
Donald DuBois wrote:
> How does one get a vector to distribute over
> a list of vectors under multiplication?
>
> For example:
>
> {{1,2}, {3,4}, {5,6}} times {a,b} should
> equal (under this operation)
>
> {{a, 2b}, {3a, 4b}, {5a, 6b}}
>
> If {a,b} is duplicated three times one can
> use MapThread as in:
>
> MapThread[Times, {{{1, 2}, {3, 4}, {5, 6}}, {{a, b}, {a, b}, {a, b}}}]
>
> but duplicating {a,b} using Table is very slow
> when the vectors are large (consisting of thousands
> of elemets).
>
> Thanks in advance for any help you can give me.
>
> Don
>
--
Murray Eisenberg murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower phone 413 549-1020 (H)
University of Massachusetts 413 545-2859 (W)
710 North Pleasant Street fax 413 545-1801
Amherst, MA 01003-9305
- References:
- Multiplying a vector over multiple vectors
- From: Donald DuBois <donabc@comcast.net>
- Multiplying a vector over multiple vectors