{smcl}
{* *! version 1.0.1  16may2012 author: Thomas Grund}{...}
{marker topic}
{helpb nw_topical##utilities:[NW-2.7] Utilities}

{title:Title}

{p2colset 9 15 22 2}{...}
{p2col :nwsync {hline 2} Sync network with Stata variables}
{p2colreset}{...}


{title:Syntax}

{p 8 17 2}
{cmdab: nwsync} 
[{it:{help netname}}]
[{cmd:,}
{opt label}
{opt fromstata}]

{synoptset 20 tabbed}{...}
{synopthdr}
{synoptline}
{synopt:{opt label}}sync the node labels{p_end}
{synopt:{opt fromstata}}change the direction of the sync{p_end}
{synoptline}
{p2colreset}{...}


{title:Description}

{pstd}
Networks ultimately exist as Mata matrices. However, one can also load them
as Stata variables that represent the adjacency matrix of a network 
(see {help nwload}). Normally, when a network is changed through another {help nwcommands:nwcommand} the 
Stata variables (if they exist) are automatically synced. But one can also invoke such 
a sync explicitly. Furthermore, {help nwsync} can be used to sync the other way around, i.e.
one can change the values of the Stata variables that represent the network and sync the 
network (that lives in Mata).   
 
{pstd}


{title:Options}

{phang}
{opt fromstata} Change the direction of the sync, i.e. the network is updated based on the
Stata variables that represent the network.
{p_end}

{phang}
{opt label} Sync the labels of the nodes with the Stata variable _nodelab
{p_end}


{title:Remarks}

{pstd}
One can use {help nwload} and {help nwsync: nwsync, fromstata} to replace tie values in a network. For example,
	
	{cmd:. nwuse florentine, nwclear}
	{cmd:. nwload flomarriage}
	{cmd:. replace marriage_1 = 99 in 2}
	{cmd:. nwsync flomarriage, fromstata}	

{pstd}
However, the preferred method to change the same tie value would be using {help nwreplace} instead:
 	
	{cmd:. nwuse florentine, nwclear}
	{cmd:. nwreplace flomarriage[1,2] = 99 }

{pstd}
The command can also be used to sync the node labels attached to a network (see also {help nwname}).

	{cmd:. nwuse florentine, nwclear}
	{cmd:. nwload flomarriage}
	{cmd:. replace _nodelab = "Peter" in 9}
	{cmd:. nwsync flomarriage, fromstata label}
	
{pstd}
Notice that the last sync can also be done with

	{cmd:. nwname flomarriage, newlabsfromvar(_nodelab)}

	
{title:See also}

	{help nwload}, {help nwreplace}, {help nwname}