On Thu, Feb 9, 2012 at 8:09 AM, Hui Zhang <span dir="ltr">&lt;<a href="mailto:buyong.huier@gmail.com">buyong.huier@gmail.com</a>&gt;</span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi,<br>
<br>
Is sparsity of Vec exploited in MatMult? I&#39;m implementing some domain decomposition<br>
methods. The residual is non-zero or significant only at very few nodes. Does<br>
MatMult knows that most entries of the Vec are zeros? Is there a threshold to<br>
regard an value as zero?<br></blockquote><div><br></div><div>No.</div><div><br></div><div>  Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Thanks,<br>
Hui</blockquote></div><br><br clear="all"><div><br></div>-- <br>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>
-- Norbert Wiener<br>