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<blockquote type="cite"
cite="mid:2928b861-f54f-42ed-90f0-94ba7eff3ec6@ecere.com">
<div class="moz-signature"> We will surely find out when we run
the unit tests for those projections?</div>
</blockquote>
<p>Not sure which tolerance they have and how much those projections
are tested (do not forget that much of the regression test suite
was automatically generated with the results PROJ produced at that
time, so with quite generic tolerances, etc.). I was more thinking
about manually testing with proj/cct binaries before and after,
and see the differences<br>
</p>
<blockquote type="cite"
cite="mid:2928b861-f54f-42ed-90f0-94ba7eff3ec6@ecere.com">
<div class="moz-signature"><br>
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<div class="moz-signature">
<blockquote type="cite">
<p>It is also not immediately obvious to me to correlate your
proposed code with the formulas in the paper by just
starring at both at the same time. Looks like some
"interpretation" of the paper has been done. </p>
</blockquote>
</div>
<div class="moz-signature">It's quite straightforward, but
optimized for the precalculations like PROJ was doing in <i>auth.cpp</i>.
There is no "interpretation" involved.<br>
</div>
</blockquote>
Well, what you mention below is what I call "interpretation", that
is not direct copying of ready-made formulas, where someone
unqualified could trivially check if there's no typo ;-)<br>
<blockquote type="cite"
cite="mid:2928b861-f54f-42ed-90f0-94ba7eff3ec6@ecere.com">
<div class="moz-signature"> </div>
<br>
<div class="moz-signature"><br>
</div>
<div class="moz-signature">It is of course still possible that I
made a mistake with all this, but I imagine that updating this
and running the tests should help to be confident about the
results.<br>
</div>
</blockquote>
<p>Running the existing PROJ test suite will show if the new
formulas are consistent with the current less precise ones with
maybe a quite loose tolerance, not necessarily that we reach the
new level of precision we claim. Hence comparing with some random
test points against GeographicLib which can hopefully be
considered as a reference implementation, to check we have
identical results (or at least share more common decimals up to
the desired precision)</p>
<br>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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