petern48 commented on PR #2529:
URL: https://github.com/apache/sedona/pull/2529#issuecomment-3590761875
> Would it be acceptable to change our comparison from equals_exact to
equals for polygons, so that we check geometric equality rather than strict
vertex order? Or is there a recommended workaround for this situation, or
something I might be missing in our test setup?
The issue is not whether we're using `equals_exact()` or `equals()`. If you
give it a try, you'll see that the comparison fails either way. Despite the
name, equals_exact is actually more lenient, since it supports a tolerance
parameter.
<details>
<summary>Script to test using equals instead</summary>
```
import shapely
geom1 = shapely.wkt.loads("POLYGON ((1 4, 3 4, 4 4, 3 1, 4 0, 0 0, 1 1, 0 4,
1 4))")
geom2 = shapely.wkt.loads("POLYGON ((1 4, 3 4, 4 4, 4 0, 3 1, 0 0, 1 1, 0 4,
1 4))")
print(geom1.equals(geom2)) # False
print(geom1.equals_exact(geom2, 0.000001)) # False
```
</details>
<details>
<summary>Images to visualize the different results </summary>
<img width="639" height="182" alt="image"
src="https://github.com/user-attachments/assets/061a5266-56f4-4a8f-a247-c9ed9d9ba683";
/>
<img width="654" height="193" alt="image"
src="https://github.com/user-attachments/assets/e3591281-e3d3-48e2-8ad8-1c7ef1e52cde";
/>
</details>
As you can see above, these geometries actually are different. Why this is
happening, I'm not sure. It could either be a bug in Sedona's function or a
difference in algorithms or edge case behaviors. If it's a significant bug, we
may want to hold off. If it's a reasonable difference in behavior that's still
correct, we can add a note in the docs and merge this anyway. Either way, we
need to understand what's happening before merging. I encourage you to
investigate, though you're not obligated to, of course, and can continue with
something else instead.
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