`my_qammod' undefined near line ...

[Ashok Kumar]

Hi,
I am using Octave with QtOctave.
I got the following error message when I called the library function 'qamdemod'.
What could be the problem?

debug> error: `my_qammod' undefined near line 35 column 9

error: evaluating assignment _expression_ near line 35, column 7

error: called from `qamdemod' in file `C:\Octave\QtOctave\octave\share\octave\p

ackages\communications-1.0.4\qamdemod.m'

Thanks and Regards
Ashok