writing proc avg in tcl script in ns2_new

I wrote a scenario in ns2 software that has 5 fixed nodes and 1 mobile sink. The mobile sink should collect the nodes' information. I want to calculate the mean avg (energy_level ,number of nodes & traffic's data on nodes) and store it in the mobile sink. The my code that I wrote does not any error but it does not print out. My code & trace file are in attachment I have to calculate this avg with proc in tcl script code not with awk code.Please help me.

    proc create_common_app {destination_id disseminating_type disseminating_interval energy_level } {
    global val
    #puts "executing create_common_app\n"
    if { $val(commonApp) == "Application/SensorBaseApp/CommonNodeApp" }
    {
			  set app_ [new $val(commonApp)]
			  $app_ set destination_id_ $destination_id
    }
    $app_ set disseminating_type_ $disseminating_type
    $app_ set disseminating_interval_ $disseminating_interval
    $app_ set energy_level _ $energy_level
    return $app_
}
proc create_mobile_sink_app { source _id disseminating_type disseminating_interval energy_level outside_network} {
    global val
    set app_ [new $val(sinkApp)]
    $app_ set source _id _ $source _id
    $app_ set disseminating_type_ $disseminating_type
    $app_ set disseminating_interval_ $disseminating_interval
    $app_ set energy_level _ $energy_level
    $app_ set outside_network_ $outside_network
  #$app_ set avg_ $avg
     return $app_
}
#########################################################################
#Me
####################################################################
proc avg { energy_level nn disseminating_interval  } {
  set avgen 0
  for {set i 0} {$i < 5} {incr i} {
  set $avgen [expr $energy_level(i) + $avgen ]
    }
   set $avgen [expr $avgen / $nn]
   return $avgen
	set xl [list  $avgen $nn $disseminating_interval]
 }

proc ArithmeticMean { $xl } {
    set length [llength $xl]
    if {$length == 0} {
        return 0.0
    }
    set sum [::tcl::mathop::+ {*}$xl]
    return [expr {double($sum) / $length}]
    set avgt [expr {double($sum) / $length}]
    puts "average is $avgt_"
}
#####################################################################

tracefile

   
M 0.00000 0 (9.00, 5.00, 0.00), (0.00, 0.00), 0.00
s 5.000000000 _1_ AGT  --- 0 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [0] 0 0
r 5.000000000 _1_ RTR  --- 0 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [0] 0 0
s 5.000000000 _1_ AGT  --- 1 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [1] 0 0
r 5.000000000 _1_ RTR  --- 1 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [1] 0 0
s 5.000000000 _1_ AGT  --- 2 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [2] 0 0
r 5.000000000 _1_ RTR  --- 2 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [2] 0 0
s 5.000000000 _1_ AGT  --- 3 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [3] 0 0
r 5.000000000 _1_ RTR  --- 3 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [3] 0 0
s 5.000000000 _1_ AGT  --- 4 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [4] 0 0
r 5.000000000 _1_ RTR  --- 4 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [4] 0 0
s 5.000000000 _1_ AGT  --- 5 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [5] 0 0
r 5.000000000 _1_ RTR  --- 5 cbr 150 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [5] 0 0
s 5.000000000 _1_ AGT  --- 6 cbr 100 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [6] 0 0
r 5.000000000 _1_ RTR  --- 6 cbr 100 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:0 2:0 32 0] [6] 0 0
s 5.000000000 _1_ RTR  --- 0 AODV 48 [0 0 0 0] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:255 -1:255 30 0] [0x2 1 1 [2 0] [1 4]] (REQUEST)
s 5.000535000 _1_ MAC  --- 0 AODV 106 [0 ffffffff 2 800] [energy 0.050000 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:255 -1:255 30 0] [0x2 1 1 [2 0] [1 4]] (REQUEST)
N -t 5.000535 -n 0 -e 0.049980
N -t 5.000535 -n 4 -e 0.049980
N -t 5.000535 -n 2 -e 0.049980
N -t 5.000535 -n 3 -e 0.049980	
r 5.001383005 _0_ MAC  --- 0 AODV 48 [0 ffffffff 2 800] [energy 0.049980 ei 0.000 es 0.000 et 0.000 er 0.000] ------- [1:255 -1:255 30 0] [0x2 1 1 [2 0] [1 4]] (REQUEST)
r 5.001383013 _4_ MAC  --- 0 AODV 48 [0 ffffffff 2 800] [energy 0.049980 ei 0.000 es 0.000 et 0.000 
.
.
.....

Solution

proc avg { energy_level nn disseminating_interval  } {
  set avgen 0
  for {set i 0} {$i < 5} {incr i} {
  set $avgen [expr $energy_level(i) + $avgen ]
    }
   set $avgen [expr $avgen / $nn]
   return $avgen
    set xl [list  $avgen $nn $disseminating_interval]
 }

Notes:

You can't pass arrays by value: you need to pass the array name and use upvar to connect the name to the actual array in the caller's context
Use braces around your expr expressions.
You need to dereference $i in the array expansion.
Don't use $ in the first argument to set
do you want to use $nn in the for loop, or the hard-coded value 5?

Corrected code

proc avg { energy_level_var nn disseminating_interval  } {
    upvar 1 $energy_level_var energy_level
    if {$nn == 0} {
        error "denominator cannot be zero"
    }
    set sum 0
    for {set i 0} {$i < $nn} {incr i} {
        set sum [expr {$energy_level($i) + $sum}]
    }
    return [expr {$sum / $nn}]
}

And call like this

array set energy_level {0 1.0 1 1.1 2 1.2 3 1.3 4 1.4 5 1.5}
puts "average is: [avg energy_level 6 "?"]"         ;# average is: 1.25

Also, don't use $ in the declaration of the ArithmeticMean proc:

proc ArithmeticMean { xl } {