<div dir="ltr">At each iteration of the primal-dual interior point method, a large, dense, symmetric and positive definite system of equations is solved to obtain the steps deltaX, deltay, and deltaZ. When this error case occurs, it indicates that this system of equations is singular and can't be solved. <div><br></div><div>This could be the result of a bug in CSDP or a problem with the formulation of your SDP. If you would be willing to send me a copy of the problem on which this error occurs, I'd be happy to investigate the cause. <br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Dec 4, 2014 at 3:59 PM, <span dir="ltr"><<a href="mailto:markisus@gmail.com" target="_blank">markisus@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div><div>What does this error mean? Which matrix is the system matrix and why would singularity be a problem?</div><div><br></div><div>If it helps, here is my input file:<br></div></div><div><div><a href="http://pastebin.com/ite3C1Vz" target="_blank">http://pastebin.com/ite3C1Vz</a><br></div></div>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature">Brian Borchers <a href="mailto:borchers@nmt.edu" target="_blank">borchers@nmt.edu</a><br>Department of Mathematics <a href="http://www.nmt.edu/~borchers/" target="_blank">http://www.nmt.edu/~borchers/</a><br>New Mexico Tech Phone: (575) 322-2592<br>Socorro, NM 87801 FAX: (575) 835-5366</div>
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