|
|
Ublas : |
Subject: Re: [ublas] Accessing the indices of non-zero elements in a UBLAS sparse vector
From: Tarek Elsayed (t.elsayed_at_[hidden])
Date: 2011-09-21 13:02:21
Thanks Oswin,
I think this should be included in the documentation, (See
here<http://stackoverflow.com/q/7501996/894755>).
Beginners like me can't find this easily.
I didn't understand your note about const_iterator.
Regards,
Tarek
On Wed, Sep 21, 2011 at 6:47 PM, Oswin Krause <
Oswin.Krause_at_[hidden]> wrote:
>> Hello,
>> How can I know the index of the first non-zero element in a
>> sparse_vector in ublas and each subsequent nonzero element as well?
>> The function begin() gives me an iterator that can be used to know the
>> first non-zero value stored, not its index in the vector.
>> Tarek
> Iterators offer a method index() which returns the desired result. But
> remember that only the const_iterator is really sparse!
>
> for(SparseVector::const_iterator pos = sparseVec.begin(); pos !=
> sparseVec.end();++pos){
> std::cout << pos.index()<< " "<< *pos;
> }
>
> Greetings,
> Oswin
>
> _______________________________________________
> ublas mailing list
> ublas_at_[hidden]
> http://lists.boost.org/mailman/listinfo.cgi/ublas
> Sent to: t.elsayed_at_[hidden]
>