Info Tcl and OTcl Tutorial For NS2 -Loops and Conditional Statements

For loops

For loops are very useful in ns and can be used in conjunction with arrays to easily create larger network topologies. To generate 100 nodes, the following code can be used:

for {set i 0}{$i < 100}{incr i} {
    set n($i) [$ns node]
}

While loops

These are very similar to for loops. The syntax is

set i 0
while {$i < 10} {
    set n($i) [new Node]
    incr i
}

If statements

If statements are very simple

if {$i < 10} {
    puts "i is less than 10"
}
if {$var2 == "Tcl Variable 2"} {
    puts "var2 = Tcl Variable 2"
}