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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='color:#1F497D'>Hi Dennis,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Thanks for your detailed explanation of the “bin_sum”. <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I have used the “ESMF_Regridding” functions to regrid Global Emissions data in fine rectilinear grid to Regional scale in coarser rectilinear grid. I thought there are some interpolations happens during the regridding. Since I am regridding the population data, which needs to sum up the data in fine resolution into a coarse resolution, I hesitate to use the ESMF regridding function again. However, thanks for your advice, I will check whether Example_9 works for my case. I also found the this function “rgrid2rcm”, and I will also double –check about that. <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Have a good night! <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Yuqiang<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><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"'> ncl-talk-bounces@ucar.edu [mailto:ncl-talk-bounces@ucar.edu] <b>On Behalf Of </b>Dennis Shea<br><b>Sent:</b> Wednesday, October 22, 2014 4:50 PM<br><b>To:</b> Yuqiang Zhang<br><b>Cc:</b> ncl-talk@ucar.edu<br><b>Subject:</b> Re: [ncl-talk] Regridding from fine Rectilinear data to coarse curvilinear grid<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal style='margin-bottom:12.0pt'>The 'bin_sum' function was developed to process multiple satellite swaths onto a *rectilinear* grid. Each swath's latitude and longitude arrays are typically 2-dimensional (think, curvilinear). Hence: curvilinear ==> rectilinear. More specifically, the ndtooned function is used on the lat2d, lon2d and data array so, internally the data are treated as random. The reason for confining the output to a rectilinear grid is that a simple 'location finding' algorith is used to determine the location of each input data.<o:p></o:p></p></div><div><p class=MsoNormal>You have 'shoe-horned' the 'bin-sum' function to do just the opposite. Yes, it works BUT you are invoking the function for EACH 'fine resolution' grid point via the double do-loop. EACH invocation requires the underlying code to reinitialize. This imposes a huge penalty.<br><br>===<o:p></o:p></p></div><div><p class=MsoNormal>The procedure can go fron one rectilinear grid to another.<o:p></o:p></p></div><div><p class=MsoNormal>An example of going from an input high ('fine') resolution rectilinear grid to an output coarser rectilinear grid is<br><br><a href="http://www.ncl.ucar.edu/Applications/binning.shtml">http://www.ncl.ucar.edu/Applications/binning.shtml</a><o:p></o:p></p></div><div><p class=MsoNormal>Example 3<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><br>===<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>It may be best to use ESMF Regridding<br><br><a href="http://www.ncl.ucar.edu/Applications/ESMF.shtml">http://www.ncl.ucar.edu/Applications/ESMF.shtml</a><o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>See: Example 9<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>Likely, 'conservative remapping' is what you want<o:p></o:p></p></div><div><p class=MsoNormal>So, your 'src' (source) information is the rectilinear data.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>The 'dst' (destination) is the curvilinear grid.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>Note: the weight file need be generated only once. Subsequently, you can reuse it.<o:p></o:p></p></div><div><p class=MsoNormal>Good Luck<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Tue, Oct 21, 2014 at 9:31 PM, Yuqiang Zhang <<a href="mailto:yuqiangzhang.thu@gmail.com" target="_blank">yuqiangzhang.thu@gmail.com</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hi All,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I need to regrid the population data from fine rectilinear grid to coarse curvilinear grid. <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Procedure “bin_sum” will not work very efficiently for me, as <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Bin_Sum<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>“ gbin [*][*] : numeric , <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> gknt [*][*] : integer , <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <b>glon [*] : numeric , </b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b> glat [*] : numeric , </b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> zlon [*] : numeric , <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> zlat [*] : numeric , <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> z [*] : numeric ”<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>The targeted output “glon” and “glat” are one-dimension and need to be equals to the rightmost and leftmost dimension of the gbin. However, I need all of them at the same dimension (lat2d, lon2d). What I am doing right now is loop over each grid cell, and then apply the “bin_sum” procedure. It works fine, but just run very slowly. I copied part of my scripts down here:<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>;*****************************************************************</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>; Variables to hold binned quantities</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>;*****************************************************************</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gbin = new ( (/nlat,mlon/), float )</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gknt = new ( (/nlat,mlon/), integer)</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> </span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gbin_temp = new ((/1, 1/), float )</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gknt_temp = new ((/1, 1/), integer)</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> </span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gbin_temp = 0.0 ; initialization</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gknt_temp = 0</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> </span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> printVarSummary(gbin_temp)</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>;*****************************************************************</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>;loop over the all the latitude and longitude in target grid</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>do I = 0, mlon-1</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> do J = 0, nlat-1</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> bin_sum(gbin_temp,gknt_temp, glon(J,I), glat(J,I), ndtooned(zlon2d), ndtooned(zlat2d), ndtooned(z) )</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> </span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> gbin(J, I) = gbin_temp(0,0)</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> end do</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'> print("zyq finish "+ I)</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-family:"Arial","sans-serif"'>end do</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Any one has the idea to improve this? <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Thanks for all your time! <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Regards,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Yuqiang <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Regards,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Yuqiang<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><br>_______________________________________________<br>ncl-talk mailing list<br>List instructions, subscriber options, unsubscribe:<br><a href="http://mailman.ucar.edu/mailman/listinfo/ncl-talk" target="_blank">http://mailman.ucar.edu/mailman/listinfo/ncl-talk</a><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>