Hi all, Peter and I did a bit of brainstorming on these predicates and we'd like to share our thoughts.
1) Two additional predicates "starting-with" and "ending-with" would be nice. These would address the cse where an annotation X is covered by an annotation Y and X has the same begin or end as Y. 2) The most part of our attention went towards the handling of cases where annotations have a width of zero. In my original proposal, I suggested e.g. that a zero width annotation at [5-5] should be either considered to be within the interval [..-5] or within [5-..] but not in both. This leads to some level of assymetry in the predicate matrix. E.g. Z3) X: [0-0] Y: [0-3] -- X-is-overlapping-with-Y, X-is-covered-by-Y Z4) X: [3-3] Y: [0-3] -- X-is-right-of-Y, X-is-right-adjacent-to-Y Z5) X: [0-3] Y: [0-0] -- X-is-overlapping-with-Y, X-is-covering-by-Y Z7) X: [0-3] Y: [3-3] -- X-is-left-of-Y, X-is-left-adjacent-to-Y However, this assymetry allows the case where two zero-width annotations are at the same location to be intuitively sane: Z11) X: [0-0] Y: [0-0] -- X-collocated-with-Y, X-is-covering-Y, X-is-covered-by-Y, X-is-overlapping-with-Y Peter instead suggested a symmetric approach where [5-5] would be considered to be within [..-5] as well as within [5-..]. This would lead to a changed matrix as follows: Z3*) X: [0-0] Y: [0-3] -- X-is-overlapping-with-Y, X-is-covered-by-Y, X-is-left-of-Y, X-is-left-adjacent-to-Y Z4*) X: [3-3] Y: [0-3] -- X-is-overlapping-with-Y, X-is-covered-by-Y, X-is-right-of-Y, X-is-right-adjacent-to-Y Z5*) X: [0-3] Y: [0-0] -- X-is-overlapping-with-Y, X-is-covering-by-Y, X-is-right-of-Y, X-is-right-adjacent-to-Y Z7*) X: [0-3] Y: [3-3] -- X-is-overlapping-with-Y, X-is-covering-by-Y, X-is-left-of-Y, X-is-left-adjacent-to-Y This would mean that the predicates could be implemented in a simpler way considering just the begin and end positions instead of also considering the width. E.g. a predicate such as right-of could simply be implemented as [Peter] right-of: X.begin >= Y.end : left-of: X.end <= Y.begin : (other predicate conditions omitted for the moment) Whereas in my proposal, it would be more complex (although surprisingly symmetric if we look at the conditions): [Richard] right-of: X.begin >= Y.end && X.begin != Y.begin : left-of: Y.begin >= X.end && X.begin != Y.begin : (other predicate conditions omitted for the moment) In Peter's version, X would be right-of/left-of Y if X and Y have the same position (e.g. [0,0]). In my version, X would NOT be right-of/left-of Y if X and Y have the same position (e.g. [0,0]). The feeling is that the symmetric approach may be more sound. It is motivated by the idea that a zero-length interval should have all the properties it would have if it were just slightly wider. So say we want to know the properties of the interval X [1,1], then we'd check at what would happen if we took X [0.5-1.5] and reduced its width. Something along these lines: X: [ 1-1.5] Y: [1,2] -- X-is-overlapping-with-Y, X-is-covered-by-Y X: [0.5-1 ] Y: [1,2] -- X-is-left-adjacent-to-Y, X-is-left-of-Y X: [1,1] Y: [1,2] -- X-is-overlapping-with-Y, X-is-covered-by-Y, X-is-left-adjacent-to-X, X-is-left-of-Y Finally, following the symmetric approach leads to Z11 becoming a singularity in which all the predicates match: Z11*) X: [0-0] Y: [0-0] -- X-is-left-of-Y, X-is-right-of-Y, X-is-left-overlapping-with-Y, : X-is-right-overlapping-with-Y, X-is-overlapping-with-Y, : X-is-collocated-with-Y, X-left-adjacent-to-Y, X-right-adjacent-to-Y, ... We have added the alternative Z4*, Z7* and Z11* to the Google Sheet for comparison. https://docs.google.com/spreadsheets/d/1fgMbqVlxwJSBNui7Y_phtRYEhzr_rfXQ5ZUREH1-nwI/edit#gid=0 @Peter: Did I sum it up about right? Any thoughts? -- Richard
