Re: Getting coordinates of array member
- To: mathgroup at smc.vnet.net
- Subject: [mg26265] Re: [mg26247] Getting coordinates of array member
- From: "Gareth J. Russell" <russell at cerc.columbia.edu>
- Date: Sun, 10 Dec 2000 00:19:38 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Stephane, you don't really need to define your own functions: Mathematica
has them already.
Note though, that it is conventional for matrix indices to indicate the row
first, and then the column, so your example is incorrect.
In[6]:=
data = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}
Out[6]=
{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}
In[7]:=
data[[1, 3]]
Out[7]=
3
In[8]:=
Position[data, 7]
Out[8]=
{{3, 1}}
on 12/6/00 2:16 AM, Stephane Hebert at stephhebert at yourpants~videotron.ca
wrote:
> Ok, let's say I have this
>
> 1 2 3
> -----------
> 1| 1 2 3
> 2| 4 5 6
> 3| 7 8 9
>
> A 3x3 matrice or array. Each number in the array represents its' position
> from top left to bottom right.
>
> What I need to do is:
>
> Find what position 1,3 is. Just by looking at the array, we find that 7 is
> the answer.
>
> Find what are the coordinates of 7. Again just by looking at the array we
> see that the answer is 1,3
>
> I need to come up with a simplu function that will return these.
>
> pos = GetPos(x,y)
>
> coord = GetCoord(pos)
>
> I've done this before, way long ago and can't find it.
==================================================
Dr. Gareth J. Russell
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