Re: How to construct symmetric matrix from just a one half
- To: mathgroup at smc.vnet.net
- Subject: [mg110408] Re: How to construct symmetric matrix from just a one half
- From: Srikanth K S <sriperso at gmail.com>
- Date: Wed, 16 Jun 2010 05:42:41 -0400 (EDT)
*Here it is:
mat1 + Transpose[mat1] - DiagonalMatrix[Diagonal[mat1]]
*---
2010/6/15 Srikanth K S <sriperso at gmail.com>
> *Sorry, that seems like a mistake!
> *---
>
>
> 2010/6/15 Srikanth K S <sriperso at gmail.com>
>
> *Here is a way, but there could be other elegant ways than this!
>>
>> *In[8]:== mat1=={{1,0,0,0},{2,3,0,0},{4,9,5,0},{2,2,3,4}};
>> In[12]:== Union@@@MapThread[List,{mat1,MapThread[List,mat1]}]
>> Out[12]== {{0,1,2,4},{0,2,3,9},{0,3,4,5,9},{0,2,3,4}}*
>> *---
>>
>>
>> 2010/6/15 dragec <culinovic at gmail.com>
>>
>> 1 0 0 0
>>> 2 3 0 0
>>> 4 9 5 0
>>> 2 2 3 4
>>>
>>
>>