Interesting behaviour indeed. I have a partial copy of the vector too when using std::copy.<br><br>However may I suggest that way:<br><br>    vect = row(mat,0);<br>    std::cout&lt;&lt;&quot;is this the first row?\n&quot;&lt;&lt;vect&lt;&lt;std::endl;<br>

<br>    vect = row(mat,mat.size1()-1);<br>    std::cout&lt;&lt;&quot;is this the last row?\n&quot;&lt;&lt;vect&lt;&lt;std::endl;<br><br>Using the free function row, it works pretty well.<br><br>David<br><br><div class="gmail_quote">

On Mon, May 17, 2010 at 23:03, Andrea Cassioli <span dir="ltr">&lt;<a href="mailto:cassioliandre@gmail.com">cassioliandre@gmail.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">

Hi guys,<br>
I&#39;ve just experienced a quite silly bug. I&#39;m currently using a<br>
symmetric matrix to perform some linear algebra calculations, after<br>
that I need to copy one row at the time in a bigger vector. Till now I<br>
have been performing row copying by means of simple hand-made loops.<br>
<br>
Now I would like to clean the code, so I &#39;ve decided to use matrix_row<br>
adaptors to iterate among all matrix row and use std::copy to perform<br>
the copy operation.<br>
<br>
It sounds clean and simple but surprise it does not work! I&#39;ve write<br>
down a very simple example, which is attached to the message. In fact<br>
the copy is performed accessing the underlying triangular matrix used<br>
to store the symmetric one.<br>
<br>
I&#39;m pretty sure I&#39;m doing something wrong, but I would expect the<br>
matrix_row adaptor to behave as a normal vector, that is I would like<br>
to play with it seamlessly.<br>
<br>
Am I wrong or it is a bug??<br>
<br>
Best Regards,<br>
<font color="#888888">Andrea Cassioli<br>
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Sent to: <a href="mailto:david.bellot@gmail.com">david.bellot@gmail.com</a><br></blockquote></div><br><br clear="all"><br>-- <br>David Bellot, PhD<br><a href="mailto:david.bellot@gmail.com">david.bellot@gmail.com</a><br>

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