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<p>Le 28/03/2020 à 16:30, Even Rouault a écrit :</p>
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p, li { white-space: pre-w</style>And given that the implementation of
gnomonic is for a sphere only, the flattening of WGS84 is
ignored. So you'll get the same result as if it was a sphere of
radius 6378137 metres.</p>
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<p>Just a little note in case it may be considered worth to apply:
in situations where spherical formulas are used with an ellipsoid,
EPSG approach is often to use the authalic radius (the radius of a
sphere of same surface than the ellipsoid) instead than the
semi-major axis length.</p>
<p><a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Earth_radius#Authalic_radius">https://en.wikipedia.org/wiki/Earth_radius#Authalic_radius</a></p>
<p> Martin</p>
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