function block error- compute maximum size

Hi,

when working with matlab function block in simulink I have the q=d.*[0:n-1];

throws error,

Computed maximum size of the output of function 'colon' is not bounded. Static memory allocation requires all sizes to be bounded. The computed size is [1 x :?].Computed maximum size of the output of function 'colon' is not bounded. Static memory allocation requires all sizes to be bounded. The computed size is [1 x :?].

How can I solve this?

thanks