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/* Local incidence properties * / unicode --> html
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A '''local incidence property''' (LIP) of a relation ''L'' is a property that depends in turn on the properties of special subsets of ''L'' that are known as its ''local flags''. The local flags of a relation are defined in the following way:
A '''local incidence property''' (LIP) of a relation ''L'' is a property that depends in turn on the properties of special subsets of ''L'' that are known as its ''local flags''. The local flags of a relation are defined in the following way:
−Let ''L'' be a ''k''-place relation ''L'' ⊆ ''X''<sub>1</sub> × … × ''X''<sub>''k''</sub>.
+Let ''L'' be a ''k''-place relation ''L'' ⊆ ''X''<sub>1</sub> × … × ''X''<sub>''k''</sub>.
Select a relational domain ''X''<sub>''j''</sub> and one of its elements ''x''. Then ''L''<sub>''x''.''j''</sub> is a subset of ''L'' that is referred to as the ''flag'' of ''L'' with ''x'' at ''j'', or the ''x''.''j''-flag of ''L'', an object which has the following definition:
Select a relational domain ''X''<sub>''j''</sub> and one of its elements ''x''. Then ''L''<sub>''x''.''j''</sub> is a subset of ''L'' that is referred to as the ''flag'' of ''L'' with ''x'' at ''j'', or the ''x''.''j''-flag of ''L'', an object which has the following definition:
−:* ''L''<sub>''x''.''j''</sub> = { (''x''<sub>1</sub>, …, ''x''<sub>''j''</sub>, …, ''x''<sub>''k''</sub>) ∈ ''L'' : ''x''<sub>''j''</sub> = ''x'' }.
+:* ''L''<sub>''x''.''j''</sub> = { (''x''<sub>1</sub>, …, ''x''<sub>''j''</sub>, …, ''x''<sub>''k''</sub>) ∈ ''L'' : ''x''<sub>''j''</sub> = ''x'' }.
Any property ''C'' of the local flag ''L''<sub>''x''.''j''</sub> ⊆ ''L'' is said to be a ''local incidence property'' of ''L'' with respect to the locus ''x'' at ''j''.
Any property ''C'' of the local flag ''L''<sub>''x''.''j''</sub> ⊆ ''L'' is said to be a ''local incidence property'' of ''L'' with respect to the locus ''x'' at ''j''.