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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'>Dear Jennifer,<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'>Referencing your below reply, Am trying to use amax() with linear interpolation to the same problem (need area maximum now) But am not getting the maximum values in destination grid. I have gone throu’ the documentation <a href="http://www.iges.org/grads/gadoc/gradfunclterp.html">http://www.iges.org/grads/gadoc/gradfunclterp.html</a> but am not getting any clue that we can use amax() function with the ltrep. But when I use it not getting the maximum value’s plot in grads. Below is the command used and CTL file.<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:10.0pt;font-family:"Calibri","sans-serif"'>reinit<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>sdfopen D:/WeatherGribFiles/2014/06/11/rtofs_glo_2ds_f024_daily_prog.nc<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>open D:/WeatherGribFiles/2014/06/11/rtofs_glo_2ds_f024_daily_prog2.ctl<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>set parea 0 11 0 8.5<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>set vpage 0 11 0 8.5<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>set lon -74.16 434<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>set lat -90 90<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>set cthick 6<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>set arrscl 0.10 <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>d lterp(u_velocity.1*1.95,lat.2,amax);lterp(v_velocity.1*1.95,lat.2,amax)<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'>CTL file : <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:10.0pt;font-family:"Calibri","sans-serif"'>dset D:\WeatherGribFiles\2014\06\22\rtofs_glo_2ds_f024_daily_prog.nc<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>index D:\WeatherGribFiles\2014\06\22\rtofs_glo_2ds_f024_daily_prog_DUMMY.nc <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>title 2D Sfc Daily Prognostic 00Z22jun2014: Forecast, downloaded Jun 22 15:20 UTC <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>undef 1.26765e+30 <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>dtype netcdf <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";background:yellow;mso-highlight:yellow'>xdef 180 linear 74.16 2.0 <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";background:yellow;mso-highlight:yellow'>ydef 67 linear -90 3.0</span><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>zdef 1 linear 1 1 <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>tdef 1 linear 00Z23JUN2014 1mn<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>options template <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>vars 2 <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>u_velocity=>u_velocity 1 t,z,y,x eastward_sea_water_velocity (m/s) <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>v_velocity=>v_velocity 1 t,z,y,x northward_sea_water_velocity (m/s) <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'>endvars<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'>As I change the X def, ydef entries for the dummy destination grid size, value changes but I expect it to be max every time. Please lead me.<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><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#215868'>Thanks & Regards<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#215868'>Anil Kumar <o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#00A1DA'>OceanManager</span></b><b><i><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#215868'> </span></i></b><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#00A1DA'>Inc.</span></b><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#009BD2'> </span></b><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#00A1DA'><o:p></o:p></span></b></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> gradsusr-bounces@gradsusr.org [mailto:gradsusr-bounces@gradsusr.org] <b>On Behalf Of </b>Jennifer Adams<br><b>Sent:</b> Thursday, May 01, 2014 9:09 PM<br><b>To:</b> GrADS Users Forum<br><b>Subject:</b> Re: [gradsusr] Help on Areal average using Grads<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hi, Anil -- <o:p></o:p></p><div><p class=MsoNormal>You need to create a new descriptor file that describes a grid you would like to be your 'destination grid'; presumably it would have grid points that correspond to every 8th grid point in your original grid. It can be a dummy descriptor -- use 'dset ^foo.dat' and 'options template' so GrADS won't care if foo.dat doesn't exist. Open both descriptors, then use lterp to regrid using the aave method:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> 'd lterp(u.1,lat.2,aave); lterp(v.1,lat.2,aave)'<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>--Jennifer<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><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On May 1, 2014, at 9:58 AM, Anil Kumar wrote:<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><div><div><div><p class=MsoNormal>Hi Grad Users,<o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal>I have NetCDF file having Ocean Current Data (attached for reference). Am using below command to display u_velocity and v_velocity and generating vector plot using SKIP() function from Grads.<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><div><p class=MsoNormal><b>reinit</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>sdfopen D:/<a href="http://rtofs_glo_2ds_f024_daily_prog.nc/">rtofs_glo_2ds_f024_daily_prog.nc</a></b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set vpage 0 11 0 8.5</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set parea 0 11 0 8.5</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set lon 74 434</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set lat -70 70</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set mproj latlon</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set display color white</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set datawarn off</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set grads off</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set timelab off</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set xlab off</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set ylab off</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set frame off</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set t 1</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set cint 40</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set display color white</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set background 0 </b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set gxout vector</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set cthick 6</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>set ccolor 1</b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b><span style='color:red'>d skip(u_velocity*1.95,8,8);skip(v_velocity*1.95,8,8)</span></b><o:p></o:p></p></div></div><div><div><p class=MsoNormal><b>printim D:\output.png x1061 y587 -t 0</b><o:p></o:p></p></div></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>output is attached and unfortunately this is not what i need exactly. It is just plotting every 8th point. I want to plot<span class=apple-converted-space> </span><b>areal average</b><span class=apple-converted-space> </span>of every 8 points and want exactly the same plot.<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal><image001.png><br><o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>NetCDF file has 4320 LON points and 2160 LAT points. The “display” command is powerful enough to iterate along the longitude and latitude. But<span class=apple-converted-space> </span><span style='color:#1F497D'><a href="http://www.iges.org/grads/gadoc/gradfuncaave.html">aave()</a></span><span class=apple-converted-space> </span>function needs fixed X and Y dimensions, no STRIDE option for X and Y.<o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div><div><p class=MsoNormal>How can I achieve this using Grads??? Ultimately I need global vector output.<o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal>Please help me on this. Thanks in advance.<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>-Anil Kumar<o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal> <o:p></o:p></p></div></div></div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif"'><rtofs_glo_2ds_f024_daily_prog.nc><output.png>_______________________________________________<br>gradsusr mailing list<br><a href="mailto:gradsusr@gradsusr.org">gradsusr@gradsusr.org</a><br><a href="http://gradsusr.org/mailman/listinfo/gradsusr">http://gradsusr.org/mailman/listinfo/gradsusr</a><o:p></o:p></span></p></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>--<o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'>Jennifer M. Adams<br>Center for Ocean-Land-Atmosphere Studies (COLA)<br>111 Research Hall, Mail Stop 2B3<br>George Mason University<br>4400 University Drive<br>Fairfax, VA 22030 <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'><o:p> </o:p></span></p></div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif";color:black'><br><br><o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>