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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'><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 style='margin-left:.5in'><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Matthew Knepley [mailto:knepley@gmail.com] <br><b>Sent:</b> Tuesday, March 25, 2014 12:50 PM<br><b>To:</b> Fischer, Greg A.<br><b>Cc:</b> petsc-users@mcs.anl.gov<br><b>Subject:</b> Re: [petsc-users] function that returns the coordinates in the DMDA group?<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p><div><div><div><p class=MsoNormal style='margin-left:.5in'>On Tue, Mar 25, 2014 at 11:41 AM, Fischer, Greg A. <<a href="mailto:fischega@westinghouse.com" target="_blank">fischega@westinghouse.com</a>> wrote:<o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Hello,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>The FAQ indicates:<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> The MPI_Cart_create() first divides the mesh along the z direction, then the y, then the x. DMDA divides along the x, then y, then z.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Is there a PETSc function call that returns the coordinates of the calling process in the DMDA group?<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>I am not sure I understand exactly what you want. Can you do a small 2D example, with 4 or 6 cells?<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><span style='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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In a 2D DMDA, my understanding is that the process ranks would be arranged as:<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'>2 3<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>0 1<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 would like to be able to call some function and have it return coordinates:<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 lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>[Rank 0] (x,y) = (0, 0)<o:p></o:p></span></p><p class=MsoNormal><span lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>[Rank 1] (x,y) = (0, 1)<o:p></o:p></span></p><p class=MsoNormal><span lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>[Rank 2] (x,y) = (1, 0)<o:p></o:p></span></p><p class=MsoNormal><span lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>[Rank 3] (x,y) = (1, 1)<o:p></o:p></span></p><p class=MsoNormal><span lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Greg<o:p></o:p></span></p><p class=MsoNormal><span lang=FR style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='margin-left:.5in'><span lang=FR> </span>Thanks,<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'> Matt<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'> <o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Thanks,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Greg<o:p></o:p></p></div></blockquote></div><p class=MsoNormal style='margin-left:.5in'><br><br clear=all><o:p></o:p></p><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><p class=MsoNormal style='margin-left:.5in'>-- <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 <o:p></o:p></p></div></div></div></body></html>