[ns] agent setting

[Rania Kamal]

hi all
i want to know what these scripts line means:-

for {set i 0} {$i < $opt(nn)} {incr i} {
$ns_ at 0.00002 "$ragent_($i) turnon"
$ns_ at 20.0 "$ragent_($i) neighborlist"
}
$ns_ at 11.0 "$ragent_(0) startSink 10.0"
$ns_ at 10.5 "$ragent_(99) startSink 10.0"
$ns_ at 25.0 "$ragent_(24) sinklist"

thanks