set a column of a matrix

Barry Smith bsmith at
Sun Nov 1 11:16:26 CST 2009

    Is your matrix dense?  If it is sparse then it doesn't make sense  
to take values from a vector (which is always dense) to a sparse matrix.


On Nov 1, 2009, at 10:57 AM, Umut Tabak wrote:

> On Sun, Nov 01, 2009 at 07:44:58AM -0600, Barry Smith wrote:
>>   MatSetValues() so long as you have good matrix preallocation this
>> will work fine.
>>   Doing a transpose is very expensive.
> Dear Barry and Matt,
>     Thanks for the replies, I am not doing anything in parallel. I
>     should use MatSetValues with appropriate column and row indices.
>     Actually, what I would like to do, I would like to set up a
>     vectorset(rectangular) and assign to a block in a matrix. Is
>     there a vectorset that I could use directly to somehow put
>     these vectors directly into this set. And use this vectorset to
>     set some part of a matrix.
>     Thanks for the advice in advance.
>     BR,
>     Umut
> -- 
> Quote:    	Coming together is a beginning, staying together is  
> progress, and working together is success.
> Author:   	Henry Ford 1863-1947, American Industrialist, Founder of  
> Ford Motor Company

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