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Hi,<br>
I have been using Gdal_Grid to interpolate LiDAR files. I use the
NN algorithm. I order to reduce any border effect, I have been
stitching all of my files together creating one big file.<br>
<br>
This created problems. The first being the GDAL_Grid had a 16mb
buffer and needed to recalculate the quad tree <span style="color:
rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;
font-style: normal; font-variant: normal; font-weight: normal;
letter-spacing: normal; line-height: 18.2px; orphans: auto;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 1; word-spacing: 0px;
-webkit-text-stroke-width: 0px; display: inline !important; float:
none; background-color: rgb(255, 255, 255);"><span
class="Apple-converted-space"> </span>for each work buffer</span>.
I was instructed to increase the buffer and to recompile Gdal_grid.<br>
<br>
These are the result for creating a NN raster using a 3 x 3 search
radius for 517 127 949 points.<br>
<br>
Gdal 1.11.2 with 16mb buffer: no results. I pulled the plug after
3 week of processing. (I had about 2 1/2 months to go!).<br>
Gdal 1.11.2 recompiled with a 1.5GB buffer: 4h46 min<br>
Gdal 2.1.0 dev released 2015/99/99 (downloaded binaries. This
version now has no need to recalculate the <span style="color:
rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;
font-style: normal; font-variant: normal; font-weight: normal;
letter-spacing: normal; line-height: 18.2px; orphans: auto;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 1; word-spacing: 0px;
-webkit-text-stroke-width: 0px; display: inline !important; float:
none; background-color: rgb(255, 255, 255);"><span
class="Apple-converted-space"></span>quad tree for each work
buffer</span>: 1h22min.<br>
<br>
This is on a Intel i7 extreme edition with 6 core + hyper threading
turned on. 64GB of ram, SSD drive. <br>
<br>
Both files look the same (will report back if not) except for the
fact that the Gdal 2.1.0 version has no data values in the file (and
the 1.11.2 version has -32768) so that is an added extra bonus.<br>
<br>
Thanks for you work.<br>
Nicolas Cadieux<br>
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