FA-70425 / GIS polygon topology / Member archive

DE-9IM matrix named predicate evaluation: touches point pair exclusion · case 05

Two points are reported as touching.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

Input [matrix, predicate, dimA, dimB] with a 9-character intersection matrix over "F012" (row-major II, IB, IE, BI, BB, BE, EI, EB, EE). Pattern characters: "*" anything, "T" any non-F value, "F" only F, "0"/"1"/"2" that exact dimension. disjoint = FF*FF****; intersects = not disjoint; touches (not both points) = FT******* or F**T***** or F***T****; within = T*F**F***; contains = T*****FF*; covers = any of T*****FF*, *T****FF*, ***T**FF*, ****T*FF*; overlaps needs equal dimensions and 1*T***T** for lines else T*T***T**; crosses = T*T****** if dimA < dimB, T*****T** if dimA > dimB, 0******** for two lines, otherwise false; equals = T*F**FFF*. Unknown predicates return None.

Why this case matters

Spatial SQL predicates, topology rules and QA checks are expressed as DE-9IM patterns; a wrong pattern changes join results silently.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression #121	`true`	`false`	Failed

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