Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Azimuthal Equidistant spherical not as accurate as ellipsoidal #1654

Closed
PositiveArrow opened this issue Oct 3, 2019 · 0 comments

Comments

@PositiveArrow
Copy link
Contributor

@PositiveArrow PositiveArrow commented Oct 3, 2019

Tested on Proj 6.2.0.

echo -120.234501 30.234501 0 | ./src/.libs/proj +proj=aeqd +a=6371008.771415 +b=6371008.771415 +lat_0=30.2345 +lon_0=-120.2345
0.00 0.00 0
echo -120.234501 30.234501 0 | ./src/.libs/proj +proj=aeqd +a=6371008.771415 +b=6371008.7714149 +lat_0=30.2345 +lon_0=-120.2345
-0.10 0.11 0

In the first command we have a==b which seems to go through the spherical support in aeqd.cpp. In the second command, b is an epsilon smaller which triggers the ellipsoidal code path.

I would expect the first command to return something similar to the second one.

rouault added a commit to rouault/PROJ that referenced this issue Oct 3, 2019
…case when the point coordinates are super close to the origin (fixes OSGeo#1654)
@rouault rouault closed this in 9b56140 Oct 4, 2019
rouault added a commit that referenced this issue Oct 4, 2019
aeqd: for spherical forward path, go to higher precision ellipsoidal case when the point coordinates are super close to the origin (fixes #1654)
backporting bot pushed a commit that referenced this issue Oct 4, 2019
…case when the point coordinates are super close to the origin (fixes #1654)
rouault added a commit that referenced this issue Oct 4, 2019
[Backport 6.2] aeqd: for spherical forward path, go to higher precision ellipsoidal case when the point coordinates are super close to the origin (fixes #1654)
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
1 participant
You can’t perform that action at this time.