Why do I receive an error when I set the initial condition of the DELAY block to complex value in Simulink 7.1 (R2008a)?

When I feed a real signal into a DELAY block from the Signal Processing Blockset with initial condition set to a complex value, the following error occurs during model update:

 Error reported by S-function 'sdspdelay' in 'twodelays_repel_complex_ics/Delay0':

 Cannot have complex ICs when output port is real-valued.

The error also occurs for Integer Delay block from the Simulink Blockset Library.

I expect seamless acceptance of real/complex mixture just as has always been the case with MATLAB. I should be free to launch a complex initial value followed by a stream of real values.

Answer 1

[MathWorks Support Team]

The ability to accept complex initial condition and real input signal for the DELAY and INTEGER DELAY blocks is not available in Simulink 7.1 (R2008a).

As a workaround, convert the input signal to a complex signal before feeding it into the delay block.