Enhance precision of inverse Spherical Mercator projection near the equator #931
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kbevers
reviewed
Apr 14, 2018
src/PJ_merc.c
Outdated
| static double hpip2atanexp(double x) { /* M_HALFPI - 2. * atan(exp(x)) */ | ||
| if (fabs(x) <= DBL_EPSILON) { | ||
| /* atan(exp(x)) can be approximated by (exp(x)-1)/2 + pi/4 */ | ||
| return -expm1x(x)); |
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The extra ) at the end here causes the build failure.
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Some tests are failing now because of the small numerical variations. I'll take a look at that in the next few days, tests should be adjusted with great care. |
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I wouldn't call ~200 m small deviations :-) It seems to be a matter of getter the sign correct on the northing. Probably just a missed minus somewhere. |
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Superseded by #1105 |
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This is for consistency with #928