Fcn block and complex number

Hi ,

I am new to simulink so trying out.

I connected a DQPSK Modulator block --> Fcn Block --> DQPSK Demodulator block. With u as input to Fcn,

I tried real(u) + i*imag(u)

I get the following error:

The expression: real(u) + i*imag(u)
in 'commexperiment1/Fcn'
has a syntax error

Question :

1. What is wrong with the syntax?
2. I dont have MEX so Matclab Function block fails as well.

Is there any other way to add custom functions in simulink?

thanks Venkatesh

[Azzi Abdelmalek]

I don't see any error. Post the entire function