Re: HoldForm
- To: mathgroup at smc.vnet.net
- Subject: [mg68100] Re: HoldForm
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Mon, 24 Jul 2006 00:55:41 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <e9v992$gjr$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Bruce Colletti wrote:
> Re Mathematica 5.2.0.0.
>
> This code displays the component differences of matrix subtraction (A-B):
>
> A = {{1, 2}, {3, 4}};
>
> B = {{5, 6}, {7, -8}};
>
> Map[MapThread[HoldForm[#1 - #2] &, {A[[#]], B[[#]]}] &, Range@2]
>
> As desired, the output is {{1 - 5, 2 - 6}, {3 - 7, 4--8}}.
>
> Two questions:
>
> - What's a better way to do this?
>
> - How can I replace the -- by +?
>
> Thankx.
>
> Bruce
>
>
A simpler approach that my preceding post is
MapThread[TraditionalForm[HoldForm[#1] - #2] &, Flatten /@ {A, B}]
that returns {1 - 5, 2 - 6, 3 - 7, 4 + 8}.
Regards,
Jean-Marc