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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Friends,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I am trying to compile a knowledge base on what could be typical expectations for the number of iterations that one could see in real-life well-conditioned CG, GMRES, and general Krylov problems.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I understand that the number of iterations will vary substantially depending on problem size, matrix structure, condition numbers, quality of preconditioners, etc. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>It would be of great value to have an idea of what to expect and under which circumstances, driven by previous experience.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If you send me a quick note with your experience on number of iterations as matrix size and other circumstances vary, I promise I will compile all the info that I receive from the group and send a summary report to the whole group. (please try to include problem type and the things that you notice in your experience that affect the number of iterations the most). The main interest is on instances that are/were useful for real life problems – for example, please do not include studies where you extended artificially the number of iterations to analyze the algorithm or learn things about the convergence.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks in advance for your contribution.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> Juan<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:18.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Juan Gonzalez, Ph.D.<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>President & Chief Scientist<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Accelogic LLC<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>13680 NW 14<sup>th</sup> St, Suite 5<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Sunrise, FL 33323<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Ph: +1.954.838.1100<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Fx: +1.954.208.0018<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:navy'><a href="http://www.accelogic.com/"><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:blue'>www.accelogic.com</span></a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img border=0 width=165 height=43 id="Picture_x0020_1" src="cid:image001.jpg@01CC7CBC.EDD61D30" alt="Description: Description: accelogic"><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#948A54'><o:p> </o:p></span></p><p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#948A54'><o:p> </o:p></span></i></p><p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#948A54'>"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty" -<o:p></o:p></span></i></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#948A54'> Sir Winston Churchill<o:p></o:p></span></p><p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Helv","sans-serif";color:#0070C0'>CONFIDENTIALITY: This email (including any attachments) may contain confidential, proprietary and privileged information, and unauthorized disclosure or use is prohibited. If you received this email in error, please notify the sender and delete this email from your system. Thank you.</span></i><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p></o:p></span></p></div></body></html>