Thread: help with network animator code

Hi im new to C, I was wondering what alterations I would need to the code to specify the upper limits of my for loops with a variable e.g instead of
{$i < 8}....something like {$i < flowno}.

Also for the for loop that specifies 4 as its upper limit, instead could I simply write flowno/2, as this loop will always be half the size of the first loop.

Code:

#Create a simulator object
set ns [new Simulator]

$ns rtproto DV
Node set multiPath_ 1


#Open the nam trace file
set nf [open out.nam w]
$ns namtrace-all $nf

#Define a 'finish' procedure
proc finish {} {
        global ns nf
        $ns flush-trace
    #Close the trace file
        close $nf
    #Execute nam on the trace file
        exec nam out.nam &
        exit 0
}



#Create the required number of nodes nodes
for {set i 0} {$i < 8} {incr i} {
  set n($i) [$ns node]
}

#set up a link between then
for {set i 0} {$i < 8} {incr i} {
  $ns duplex-link $n($i) $n([expr ($i+1)%8]) 1Mb 10ms DropTail
}

#Setting up a flow needs these four steps ---------------
#1. Create a UDP agent and attach it to node n0
for {set i 0} {$i < 4} {incr i} {
  set udp($i) [new Agent/UDP]
  $ns attach-agent $n($i) $udp($i)

#2. Create a CBR traffic source and attach it to udp0
  set cbr($i) [new Application/Traffic/CBR]
  $cbr($i) set packetSize_ 1000
  $cbr($i) set interval_ 0.05
  $cbr($i) attach-agent $udp($i)

#3. Create a Null agent (a traffic sink) and attach it to node n1
  set x [expr ($i+4)]
  set null($i) [new Agent/Null]
  $ns attach-agent $n($x) $null($i)

#4. Connect the traffic source with the traffic sink
  $ns connect $udp($i) $null($i)

#Schedule events for the CBR agent
  $ns at 0.5  "$cbr($i) start"
  $ns at 5.0 "$cbr($i) stop"

}  
#-----------------------------------------------------------

#Call the finish procedure after 1 second of simulation time
  $ns at 1.0 "finish"

#Run the simulation
  $ns run

any help is greatly appreciated!!!!!