Important: The networks package has been deprecated.  Use the superseding command GraphTheory[AddVertex] instead.

This routine adds one or more vertices to a graph. The vertex names used are returned as an expression sequence.

To force addvertex() to use a specific weight for a single vertex use the optional argument (eg. weights=3).

If more than one vertex is to be added, they can be presented as a list or set of vertices.  In this case, non-default weights must also be specified as a list of weights as in: addvertex([1, 3], weights=[0, 0], G)

A vertex cannot be a symbol or string beginning with the letter e; these are reserved, by the package, for edge names.

This routine is normally loaded via the command with(networks) but can also be referenced using the full name networks[addvertex](...).

$\mathrm{with}\left(\mathrm{networks}\right)\:$

$\mathrm{new}\left(G\right)\:$

$\mathrm{addvertex}\left(\left\{1\,2\,3\,4\right\}\,G\right)\:$

$\mathrm{addvertex}\left(\mathrm{vname}\,\mathrm{xx}\,G\right)\:$

$\mathrm{vertices}\left(G\right)$

$\left\{1\,2\,3\,4\,\mathrm{vname}\,\mathrm{xx}\right\}$

$\mathrm{vweight}\left(1\,G\right)$

$0$

$\mathrm{addvertex}\left(\left[\mathrm{n1}\,\mathrm{n2}\right]\,\mathrm{weights}=\left[5\,\mathrm{symwt}\right]\,G\right)$

$\mathrm{n1},\mathrm{n2}$

$\mathrm{vweight}\left(\mathrm{n2}\,G\right)$

$\mathrm{symwt}$