Re: iterating through the rows of a sparse matrix

[dbateman]

Tirumurti, Chandra wrote:
> 
> Hello,
> 
>  
> 
> New to Octave and loving it. I do have a question. I have a matrix X =
> 
>  
> 
> 0 1
> 
> 2 3
> 
>  
> 
> [ri, ci] = spfind(X); gives me the row indices of non-zero elements in
> ri and column indices in ci.
> 
> Is there a way to do the other way, ie, I want to get a list by row.
> 
> 

The transpose operator is quite efficient on sparse matrix and so 

[ci, ri] = spfind(X.');

is probably the easiest. There are certainly faster means that are more
complex.

D.
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