net.obs.period is an optional network-level attribute that gives meta-information about the characteristics of the observations, time range and temporal model of a networkDynamic object.
The methods (add.vertices.networkDynamic, add.edge.networkDynamic, add.edges.networkDynamic) override their network-package counterparts in order to permit assigning persistent.ids to newly-added elements if the pid is defined. They can be defined by the user with the vertex.pids argument, or, if not specified, a unique random id will be generated. (Note that any new values added by default to a vertex.names pid will not be numeric.)
These methods return either the activity spells of each vertex or edge or the unique time points at which edges and vertices become active or inactive.
A .son file is a tab-separated text file with two sections, the first describing node attribute events and the second arc attribute events. Each section has a set of defined column names as a header. See the SoNIA file specification for more information: http://sourceforge.net/apps/mediawiki/sonia/index.php?title=Son_format.
Persistent ids (pids) are unique values attached to vertices or edges which remain unchanged throughout network manipulation and extraction processes. The “vertex.pid” of a vertex is an overall data-set id, unlike the “vertex.id” which is an index dependent on network size. These functions provide ways to look up vertex.pids from vertex.ids (and the other way around) and also provide necessary modifications to some standard network functions to safely work with pids.
Converts various forms of temporal data (spell matrices, togles, lists of networks ) describing dynamics of vertices and edges into networkDynamic objects.
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