Find antipode of point(s)

Q&A
1

Does GMT have an easy way of calculating antipodes for a point(s)?

e.g.

$ echo 15 60 | gmt ~antipode~ ...
-15 240

I was skimming the gmtmath man page, but did not catch anything.

2

No, it is so simple that it hardly needs a special comment. Just change sign of the latitude and add 180 to longitude.

3

That’s what I was afraid of; Thanks Paul.