Re: how to apply Position repeatedly without a loop?
- To: mathgroup at smc.vnet.net
- Subject: [mg118649] Re: how to apply Position repeatedly without a loop?
- From: Tomas Garza <tgarza10 at msn.com>
- Date: Fri, 6 May 2011 07:21:29 -0400 (EDT)
I assume you mean r instead of elements. If such be the case, then
In[1]:= A={{1,2,3},{3,4,5},{6,7,8}};r={3,6};
In[3]:= Position[A,#]&/@rOut[3]= {{{1,3},{2,1}},{{3,1}}}
-Tomas
> Date: Thu, 5 May 2011 05:24:01 -0400
> From: steve_h44 at yahoo.com
> Subject: [mg118634] how to apply Position repeatedly without a loop?
> To: mathgroup at smc.vnet.net
>
> i have matrix A and wanted to find the Positions in this matrix of
> some elements which listed in some another vector.
>
> how to use Position to do it without a loop?
>
> I tried this:
>
> In[192]:= A={{1,2,3},
> {3,4,5},
> {6,7,8}};
> elements={3,6};
>
> Position[A,r[[1]]]
> Out[194]= {{1,1}}
>
> Position[A,r[[2]]]
> Out[197]= {{1,2}}
>
> but I want to do something like
>
> Position[A,r]
> but this does not work.
>
> I tried Map, Thread, etc.. but could not get it to work. not sure what
> the syntax is.
>
> thanks for help
> steve
>
>