Unexpected zero J-coordinate in local ijk+ when resolution > 0
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Description
Hi! I’m using H3 to assign local ijk+ coordinates to cells around a given origin.
At resolution 0, the six direct neighbors of the origin 0x8075FFFFFFFFFFF are:
(1, 0, 1)
(1, 0, 0)
(0, 1, 0)
(0, 1, 1)
(1, 1, 0)
However, when increasing resolution, for example to 2 (origin 0x82754FFFFFFFFFF), the output is:
(3, 0, 2)
(2, 0, 2)
(2, 0, 3)
(3, 0, 4)
(4, 0, 4)
(4, 0, 3)
I expected (acording to the image bellow) some of the neighbors to have a non-zero j component, but it’s always zero.
(I'm using H3 version: v4.2.1)
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Research direction
Start by reproducing the local ijk+ coordinate results described for H3 v4.2.1 at resolutions 0 and 2, using the origin and neighboring cells from the report. Trace the local ijk+ conversion entry point and compare its output with the expected coordinate interpretation shown in the linked image; done means the j component is correct for the affected neighbors.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- c
- Domain
- data
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 38/100