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New to using PostGIS and have two situations that I'm working with.

In the one case, I have a polygon that crossed the antemeridian and was detecting whether a two separate points located within that polygon one on the west and one on the east side of the antimeridian intersects with the polygon (data types used are geometries). I found I had to use the st_shift_longitude on the geometries passed to the st_intersects function.

The other situation is a polygon crossing the equator with points above and below the equator within the polygon. st_intersects doesn't detect both points intersect the polygon. Do the latitudes need to be shifted in this case? I didn't see a shift latitude function available.

I'm using the following points and polygon at the equator: st_point(170.0,45.0) st_point(170.0,-45.0)
and the polygon 'POLYGON((165 40,175 40,175 -50,165 -50,165 40))'

I'd expect that the st_intersect function return true for both points, however, it's only returning true for st_point(170.0,-45.0)

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  • Can you add the points and the polygons?
    – Ian Turton
    Commented Feb 26, 2016 at 18:45
  • FYI, "anti" = opposite versus "ante" = before.
    – mkennedy
    Commented Feb 26, 2016 at 19:33

1 Answer 1

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The maximum latitude of your polygon is 40. The latitude of your missing point is 45. I think you just have a typo in your test.

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