<div dir="ltr"><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><font color="#222222" size="2">Using python-bindings gdal.Grid() to interpolate scattered points to a regular grid using CSV and VRT for over 700,000 points. </font></span></div><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><font color="#222222" size="2"><br></font></span></div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">When testing invdist and invdistnn algorithms, invdistnn showed a decrease in performance. According to </span><span style="color:rgb(34,34,34)"><a href="https://trac.osgeo.org/gdal/ticket/6038" target="_blank"><span style="color:rgb(5,99,193);font-family:"Arial",sans-serif;font-size:10pt">https://trac.osgeo.org/gdal<wbr>/ticket/6038</span></a></span><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">, invdistnn should have improved performance.</span></div><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><font color="#000000" face="Times New Roman" size="3"></font><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">Python 3.6.4, <span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">GDAL version 2.2.2</span></span><font color="#000000" face="Times New Roman" size="3"> </font><font color="#000000" face="Times New Roman" size="3"> </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3"> </font></span></span></div><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><table style="border:currentColor;border-collapse:collapse" border="1" cellspacing="0" cellpadding="0"><tbody><tr><td width="156" valign="top" style="padding:0in 5.4pt;border:1pt solid windowtext;width:116.85pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><b><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">gdal.Grid()</font></span></b></p><font color="#000000" face="Times New Roman" size="3"></font></td><td width="156" valign="top" style="border-width:1pt 1pt 1pt 0px;border-style:solid solid solid none;border-color:windowtext windowtext windowtext rgb(0,0,0);padding:0in 5.4pt;width:116.85pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><b><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">Runtime</font></span></b></p><font color="#000000" face="Times New Roman" size="3"></font></td></tr><tr><td width="156" valign="top" style="border-width:0px 1pt 1pt;border-style:none solid solid;border-color:rgb(0,0,0) windowtext windowtext;padding:0in 5.4pt;width:116.85pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"><span style="color:black;font-family:"Calibri Light",sans-serif;font-size:11pt">invdist</span></font><font color="#000000" face="Times New Roman" size="3">   </font></td><td width="156" valign="top" style="border-width:0px 1pt 1pt 0px;border-style:none solid solid none;border-color:rgb(0,0,0) windowtext windowtext rgb(0,0,0);padding:0in 5.4pt;width:116.85pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">6 min</font></span></p><font color="#000000" face="Times New Roman" size="3"></font></td></tr><tr><td width="156" valign="top" style="border-width:0px 1pt 1pt;border-style:none solid solid;border-color:rgb(0,0,0) windowtext windowtext;padding:0in 5.4pt;width:116.85pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"><span style="color:black;font-family:"Calibri Light",sans-serif;font-size:11pt">invdistnn</span></font><font color="#000000" face="Times New Roman" size="3">   </font></td><td width="156" valign="top" style="border-width:0px 1pt 1pt 0px;border-style:none solid solid none;border-color:rgb(0,0,0) windowtext windowtext rgb(0,0,0);padding:0in 5.4pt;width:116.85pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">45 min</font></span></p><font color="#000000" face="Times New Roman" size="3"></font></td></tr></tbody></table><font color="#000000" face="Times New Roman" size="3"><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">Command Line, <span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">GDAL version 2.2.1</span></font></span></font></div><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">   </font><font color="#000000" face="Times New Roman" size="3">  </font><font color="#000000" face="Times New Roman" size="3"> </font></div><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><table style="border:currentColor;border-collapse:collapse" border="1" cellspacing="0" cellpadding="0"><tbody><tr><td width="168" valign="top" style="padding:0in 5.4pt;border:1pt solid windowtext;width:125.75pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><b><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">gdal_grid</font></span></b></p><font color="#000000" face="Times New Roman" size="3"></font></td><td width="144" valign="top" style="border-width:1pt 1pt 1pt 0px;border-style:solid solid solid none;border-color:windowtext windowtext windowtext rgb(0,0,0);padding:0in 5.4pt;width:107.95pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><b><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">Runtime</font></span></b></p><font color="#000000" face="Times New Roman" size="3"></font></td></tr><tr><td width="168" valign="top" style="border-width:0px 1pt 1pt;border-style:none solid solid;border-color:rgb(0,0,0) windowtext windowtext;padding:0in 5.4pt;width:125.75pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p style="background:white;margin:0in 11.25pt 0pt 0in"><span style="color:black;font-family:"Calibri Light",sans-serif;font-size:11pt">invdist</span></p><font color="#000000" face="Times New Roman" size="3"></font></td><td width="144" valign="top" style="border-width:0px 1pt 1pt 0px;border-style:none solid solid none;border-color:rgb(0,0,0) windowtext windowtext rgb(0,0,0);padding:0in 5.4pt;width:107.95pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">4 min</font></span></p><font color="#000000" face="Times New Roman" size="3"></font></td></tr><tr><td width="168" valign="top" style="border-width:0px 1pt 1pt;border-style:none solid solid;border-color:rgb(0,0,0) windowtext windowtext;padding:0in 5.4pt;width:125.75pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p style="margin:0in 0in 0pt"><span style="color:black;font-family:"Calibri Light",sans-serif;font-size:11pt">invdistnn</span></p><font color="#000000" face="Times New Roman" size="3"></font></td><td width="144" valign="top" style="border-width:0px 1pt 1pt 0px;border-style:none solid solid none;border-color:rgb(0,0,0) windowtext windowtext rgb(0,0,0);padding:0in 5.4pt;width:107.95pt;background-color:transparent"><font color="#000000" face="Times New Roman" size="3"></font><p align="center" style="margin:0in 0in 0pt;text-align:center"><span style="font-family:"Calibri Light",sans-serif;font-size:11pt"><font color="#000000">22 min</font></span></p><font color="#000000" face="Times New Roman" size="3"></font></td></tr></tbody></table></div><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><p style="background:white;margin:0in 0in 0pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"> </font></p><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><p style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">Python</span></p><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><p style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">ugrid_invdist = gdal.Grid('ugrid_</span><span style="color:black;font-family:"Arial",sans-serif;font-size:10pt"> invdist</span><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">.tiff<wbr>', 'gomofs_u.vrt', format='GTIFF', width=1248, height=861, algorithm="invdist:power=2.0:s<wbr>moothing=0.0:radius1=0.06:radi<wbr>us2=0.06:angle=0.0:max_points=<wbr>4:min_points=2:nodata=0.0", zfield="u")</span></p><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><p style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">ugrid_invdistnn = gdal.Grid('ugrid_</span><span style="color:black;font-family:"Arial",sans-serif;font-size:10pt"> invdistnn</span><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">.ti<wbr>ff', 'gomofs_u.vrt', format='GTIFF', width=1248, height=861, algorithm="invdistnn:power=2.0<wbr>:smoothing=0.0:radius1=0.06:ra<wbr>dius2=0.06:angle=0.0:max_point<wbr>s=4:min_points=2:nodata=0.0", zfield="u")</span></p><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><p style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">Command Line</span></p><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><p style="background:white;margin:0in 0in 0pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">gdal_grid -zfield "u" -a invdist:power=2.0:smoothing=0.<wbr>0:radius1=0.06:radius2=0.06:an<wbr>gle=0.0:max_points=4:min_point<wbr>s=2:nodata=0.0 -zfield "u" -outsize 1248 861 -of GTiff gomofs_u.vrt ugrid_</span><span style="color:black;font-family:"Arial",sans-serif;font-size:10pt">invdist</span><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">.tiff</span></p><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><font color="#000000" face="Times New Roman" size="3"></font></div><div style="background:white;margin:0in 0in 0pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">gdal_grid -zfield "u" -a invdistnn:power=2.0:smoothing=<wbr>0.0:radius1=0.06:radius2=0.06:<wbr>angle=0.0:max_points=4:min_poi<wbr>nts=2:nodata=0.0 -zfield "u" -outsize 1248 861 -of GTiff gomofs_u.vrt ugrid_</span><span style="color:black;font-family:"Arial",sans-serif;font-size:10pt">invdistnn</span><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt">.tiff</span></div></span></span><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><span><br></span></span></div><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal">Any ideas on why the performance suffers with invdistnn vs. invdist as well as Python vs. command-line?</span></span></div><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><br></span></div><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal">Thank you</span></div></span><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"></span></span></span></div><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><div class="gmail_chip gmail_drive_chip" style="padding:5px;border:1px solid rgb(221,221,221);width:396px;height:18px;color:rgb(34,34,34);line-height:1;font-family:arial;font-size:13px;font-style:normal;font-weight:bold;max-height:18px;background-color:rgb(245,245,245)"><a style="padding:1px 0px;border:currentColor;width:100%;overflow:hidden;text-decoration:none;display:inline-block;white-space:nowrap" href="https://drive.google.com/file/d/1PbT8mLKfC0TEwrCCKtZdAm9ibY4BI02y/view?usp=drive_web" target="_blank"><img style="border: currentColor; border-image: none; vertical-align: bottom;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span style="color:rgb(17,85,204);text-decoration:none;vertical-align:bottom" dir="ltr">gomofs.csv</span></a></div></div><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"></div><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><div class="gmail_chip gmail_drive_chip" style="padding:5px;border:1px solid rgb(221,221,221);width:396px;height:18px;color:rgb(34,34,34);line-height:1;font-family:arial;font-size:13px;font-style:normal;font-weight:bold;max-height:18px;background-color:rgb(245,245,245)"><a style="padding:1px 0px;border:currentColor;width:100%;overflow:hidden;text-decoration:none;display:inline-block;white-space:nowrap" href="https://drive.google.com/file/d/1dsStgDkEAX6bN4oCs2777f2TdU-76bs7/view?usp=drive_web" target="_blank"><img style="border: currentColor; border-image: none; vertical-align: bottom;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span style="color:rgb(17,85,204);text-decoration:none;vertical-align:bottom" dir="ltr">gomofs_u.vrt</span></a></div></div></span></span></span><div style="background:white;margin:0in 0in 8pt;line-height:11.75pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"><span style="color:rgb(34,34,34);font-family:"Arial",sans-serif;font-size:10pt"></span></span></span></div></span></div><div><span style="text-align:left;color:rgb(38,50,56);text-transform:none;text-indent:0px;letter-spacing:normal;font-family:Roboto,sans-serif;font-size:13px;font-style:normal;font-weight:400;word-spacing:0px;float:none;display:inline;white-space:normal"><br></span></div></div>