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<div class="moz-cite-prefix">On 11/6/20 7:07 AM, jratike80 wrote:<br>
</div>
<blockquote type="cite"
cite="mid:1604660863882-0.post@n6.nabble.com">
<pre class="moz-quote-pre" wrap="">PROJCS["WGS 84 / Pseudo-Mercator",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
TOWGS84[0,0,0,0,0,0,0],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.0174532925199433,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]],
PROJECTION["Mercator_1SP"],
PARAMETER["central_meridian",0],
PARAMETER["scale_factor",1],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
AXIS["Easting",EAST],
AXIS["Northing",NORTH],
EXTENSION["PROJ4","+proj=merc +a=6378137 +b=6378137 +lat_ts=0 +lon_0=0
+x_0=0 +y_0=0 +k=1 +units=m +nadgrids=@null +wktext +no_defs"]]
</pre>
</blockquote>
<br>
The way I handle it is (slightly older notation):<br>
<br>
<font face="monospace">PROJCS["WGS84 / Spherical Mercator",<br>
GEOGCS["WGS84basedSpheric_GCS",<br>
DATUM["WGS84basedSpheric_Datum",<br>
SPHEROID["WGS84based_Sphere", 6378137, 0]],<br>
PRIMEM["Greenwich", 0],<br>
UNIT["degree", 0.0174532925199433]],<br>
PROJECTION["Mercator"],<br>
PARAMETER["latitude_of_origin", 0],<br>
PARAMETER["central_meridian", 0],<br>
PARAMETER["false_easting", 0],<br>
PARAMETER["false_northing", 0],<br>
UNIT["meter", 1],<br>
AUTHORITY["EPSG", "3857"]]<br>
</font><br>
and my system parses this and generates:<br>
<br>
<font face="monospace">proj4-library string for coordsys (+over
suppressed):<br>
+proj=merc +nadgrids=@null +a=6378137 +b=6378137 +lat_0=0
+lon_0=0 +x_0=0 +y_0=0 +no_defs</font><br>
<br>
Will GDAL accept a "0" for the inverse of flattening to represent a
sphere?<br>
<br>
Explicitly saying that the datum/geographic coordsys is truly WGS84
is probably technically wrong.<br>
<br>
<div class="moz-signature">-- <br>
Dr. Craig S. Bruce
<br>
Senior Software Developer
<br>
CubeWerx<i> </i>Inc.
<br>
<a href="http://www.cubewerx.com/">https://www.cubewerx.com</a></div>
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