Re: Part
- Subject: [mg2894] Re: [mg2890] Part
- From: ross at zeus.mpce.mq.edu.au ("Ross Moore <ross at zeus.mpce.mq.edu.au>")
- Date: 5 Jan 1996 03:50:39 -0600
- Approved: usenet@wri.com
- Distribution: local
- Newsgroups: wri.mathgroup
- Organization: Wolfram Research, Inc.
- Sender: mj at wri.com
Hello Hans,
> w={{1,2,3},{4,5,6},{7,8,9}}
> npos={2,1}
>
> npos is the position of the element I need.
>
> w[[npos]]
>
> does not work, as it returns the second and the first
> line.
No, ...and neither should it,
since the argument is a List of integers, not a Sequence.
You want:
w[[Apply[Sequence,npos]]]
or its shorthand
w[[Sequence@@npos]]
e.g.
(Zeus2.2.2) In[8]:= w[[Sequence@@npos]]
(Zeus2.2.2) Out[8]= 4
Regards,
Ross
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Ross Moore Internet: ross at mpce.mq.edu.au
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