[sc34wg3] RM: Cx, endpoint type, i-node, node
Patrick Durusau
sc34wg3@isotopicmaps.org
Mon, 24 Feb 2003 12:51:12 -0500
REF: parid2158
TXT: A connectedness between two nodes, represented by an arc, with a
c-node as one endpoint and another node (which itself may either be
generic or of type a, c, t, or r) serving as the x endpoint. A Cx arc
specifies that a specific role player (the subject of the node that
serves as the x endpoint) is the role player in a casting (the subject
of the node that serves as the C endpoint) of that specific role player
in a specific role in a specific assertion.
FIX: An arc with a c-node as one endpoint and an x-node as the other
endpoint.
COM: Removed connectedness, see definition of edge below. Further
removed defining of the parts of the definition. The c-node and x-node
references should lead readers to the definitions of those items. Helps
prevent confusing and perhaps inaccurate restatement of the definitions
for those items.
END:
REF: parid2161
TXT: The type of an endpoint of an arc. There are five endpoint types:
FIX: Strike.
COM: The type of endpoints are defined for each node, should not be
repeated here.
END:
REF: parid2280
TXT: A: Only a-nodes serve as A endpoints.
FIX: Strike.
COM: See comment to parid2161. Note also that it is unnecessary to
repeat the "only a-nodes serve as A endpoints" mantra. The quality of
being a-node is attributed to a node by the presence of an arc in a
particular assertion and does not add anything to the explanation here.
END:
REF: parid2281
TXT: T: Only t-nodes serve as T endpoints.
FIX: Strike.
COM: See comment to parid2161. Note also that it is unnecessary to
repeat the "only t-nodes serve as T endpoints" mantra. The quality of
being t-node is attributed to a node by the presence of an arc in a
particular assertion and does not add anything to the explanation here.
END:
REF: parid2282
TXT: C: Only c-nodes serve as C endpoints.
FIX: Strike.
COM: See comment to parid2161. Note also that it is unnecessary to
repeat the "only c-nodes serve as C endpoints" mantra. The quality of
being c-node is attributed to a node by the presence of an arc in a
particular assertion and does not add anything to the explanation here.
END:
REF: parid2283
TXT: R: Only r-nodes serve as R endpoints.
FIX: Strike.
COM: See comment to parid2161. Note also that it is unnecessary to
repeat the "only r-nodes serve as R endpoints" mantra. The quality of
being r-node is attributed to a node by the presence of an arc in a
particular assertion and does not add anything to the explanation here.
END:
REF: parid2284
TXT: x: All kinds of nodes, including generic nodes, can serve as x
endpoints.
FIX: Strike.
COM: X nodes are defined elsewhere in the glossary.
END:
REF: parid2167
TXT: The i-node is an isolated node that does not serve as the endpoint
of any arc. In a well-formed topic map, an i-node must exhibit a
built-in value for at least one SIDP.
FIX: A node that does not serve as the endpoint of any arc.
COM: Removed repetition of term. Removed explanation of i-node in a
well-formed topic map as irrelevant to its definition.
END:
REF: parid2173
TXT: In a topic map graph, a proxy for a single subject. In a topic map
graph, only nodes can be the proxies of subjects (arcs cannot serve as
proxies for subjects). Nodes are sometimes also called "topics".
FIX: A proxy for a single subject.
COM: Usage of nodes in the topic map graph should occur in an
explanation of the topic map graph.
END:
REF: parid2178
TXT: Every node has named properties for which it may exhibit values.
Some properties are "Subject Identity Discrimination Properties
(SIDPs)". The values of SIDPs comprehensively and exclusively specify
the subject for which the node is a proxy; SIDP values are the only
basis for recognizing when two nodes have the same subject or different
subjects, and should therefore either be merged or left unmerged.
FIX: Strike.
COM: Properties of nodes and use of them are inappropriate here. SIDPs
are defined separately and should not be repeated here. Just bulks up
the spec with no attending increase in clarity.
END:
REF: parid2272
TXT: A node may also exhibit values for "Other Properties (OPs)". The
significances of OP values are defined by TM Applications, but, unlike
the values of SIDPs, the values of OPs do not influence the merging process.
FIX: Strike.
COM: See comments to parid2178.
END:
REF: parid2273
TXT: The values of some properties can be "built-in"; nodes that exhibit
built-in property values are defined by the governing TM Application as
being present in every topic map that conforms to the TM Application.
Other property values are "conferred" by virtue of the node's situation.
FIX: Strike.
COM: See comments to parid2178.
END:
REF: parid2279
TXT: Nodes that serve as the endpoints of arcs are said to be
"situated". Each node's situation in the topic map graph may conform to
zero or more TM Application-defined "situation features" that confer
upon it the values it exhibits for its properties.
FIX: See comments to parid2178.
COM:
END:
REF: parid2274
TXT: Some nodes are called "special" nodes, because, in addition to
being role players in zero or more assertions, they have special
functions in certain assertion(s) of which they are non-role-player
components. There are four kinds of special nodes: a-nodes, c-nodes,
r-nodes and t-nodes.
FIX: See comments to parid2178
COM:
END:
REF: parid2275
TXT: If a node is not one of the four kinds of special nodes, it is
called a "generic" node.
FIX: Strike.
COM: See comments to parid2178. Note further the confusion engendered by
the notion of "special nodes." It seems clearer to say that there are
nodes which participate in assertions and nodes that do not. Of those
that do, the arcs within particular assertions attribute roles to the
nodes in that assertion. A node that is an a-node in one assertion, may
well be a t-node in another. It is insufficiently clear that nodes are
not of some static "kind" in the current draft. It is only within a
particular assertion and then by determining the roles that the nodes
play in that assertion, that arcs can illuminate the various parts of
the assertion.
END:
REF: parid2276
TXT: A generic node may be a role player in zero or more assertions. If
a generic node is not a role player in any assertion, it is called an
"isolated" node (or i-node), because it serves as the endpoint of no
arcs whatsoever.
FIX: Strike.
COM: See comments to parid2178. I-node is defined elsewhere.
END:
REF: parid2277
TXT: "Isolated" is the opposite of "situated". Isolated nodes have no
situation features, which means that no values can be "conferred" upon
their SIDPs. This is the reason why i-nodes are not well-formed unless
they exhibit a built-in value for at least one of their SIDPs; in the
absence of such a built-in value, there would be no indication of the
subject for which an i-node is a proxy.
FIX: Strike.
COM: See comments to parid2178.
END:
REF: parid2278
TXT: Topic map authors are free to create topic maps in which all kinds
of nodes, including both generic nodes and all kinds of special nodes,
are role players in zero or more assertions.
FIX: Strike.
COM: See comments to parid2178.
END:
--
Patrick Durusau
Director of Research and Development
Society of Biblical Literature
pdurusau@emory.edu
Co-Editor, ISO Reference Model for Topic Maps