#set length 0
if { [isdraw result] } {
   #check if result is valid

   puts [checkshape result]

   set prop "length"
   set mass $length
   regexp {Mass +: +([-0-9.+eE]+)} [lprops result] full m      

   if { [string compare "$mass" "empty"] != 0 } {
      if { $m == 0 } {
       	 puts "Error : The $command is not valid. The $prop is 0."
      }
      if { $mass > 0 } {
      	 puts "The expected $prop is $mass"
      }
      #check of change of length is < 1%
      if { ($mass != 0 && [expr 1.*abs($mass - $m)/$mass] > 0.01) || ($mass == 0 && $m != 0) } {
      	 puts "Error : The $prop of the resulting shape is $m"
      }
   } else {
      if { $m != 0 } {
       	 puts "Error : The $command is not valid. The $prop is $m"
      }
   }

   if { $m > 0 } {
      smallview
      clear
      donly result
      fit
      xwd $imagedir/${test_image}.png
   } else {
      smallview
      clear
      fit
      xwd $imagedir/${test_image}.png
   }
} else {
   puts "Error : The $command cannot be built."
}

# to end a test script
puts "TEST COMPLETED"
