[Date Index]
[Thread Index]
[Author Index]
Re: How to pick all terms which have are multiplied with a factor, e.g., 2
*To*: mathgroup at smc.vnet.net
*Subject*: [mg35466] Re: How to pick all terms which have are multiplied with a factor, e.g., 2
*From*: Andrzej Kozlowski <andrzej at bekkoame.ne.jp>
*Date*: Sun, 14 Jul 2002 06:19:38 -0400 (EDT)
*Sender*: owner-wri-mathgroup at wolfram.com
I guess the simples way is something like
In[8]:=
2*a*b^2*c^3 + 13*x*y*a*b + 2/d //. 2*x_ + 2*y_ -> 2*(x + y)
Out[8]=
2*(a*b^2*c^3 + 1/d) + 13*a*b*x*y
The reason for ReplaceRepeated (//.) is that this will work with more
multiples of 2, e.g.
In[9]:=
2*a*b^2*c^3 + 13*x*y*a*b + 2/d + 2*h + 2*x^2*y^3 //.
2*x_ + 2*y_ -> 2*(x + y)
Out[9]=
13*a*b*x*y + 2*(a*b^2*c^3 + 1/d + h + x^2*y^3)
Andrzej Kozlowski
Toyama International University
JAPAN
http://platon.c.u-tokyo.ac.jp/andrzej/
On Saturday, July 13, 2002, at 04:49 PM, Matthias G. Imhof wrote:
> I would like to simplify a large symbolic summation. I know that terms
> which
> are multiplied with a common integer factor can ultimately be combined
> and
> simplified.
>
> As an example: from the sum
>
> 2 a b^2 c^3 + 13 x y a b + 2 d^-1
>
> I would like to pick 2 a b^2 c^3 + 2 d^-1 to combine them; and
> similarly for
> other common integer factors. I suspect that patterns would help, but I
> did
> not manage to devise a correct one.
>
> Matthias
>
>
>
>
Andrzej Kozlowski
Toyama International University
JAPAN
http://platon.c.u-tokyo.ac.jp/andrzej/
Prev by Date:
**Re: How to pick all terms which have are multiplied with a factor, e.g., 2**
Next by Date:
**Re: How to pick all terms which have are multiplied with a factor, e.g., 2**
Previous by thread:
**Re: How to pick all terms which have are multiplied with a factor, e.g., 2**
Next by thread:
**Re: How to pick all terms which have are multiplied with a factor, e.g., 2**
| |