setundef - replace undef values with defined constants

    setundef [options] [selection]

This command replaced undef (x) constants with defined (0/1) constants.

        also set undriven nets to constant values

        replace with bits cleared (0)

        replace with bits set (1)

    -random <seed>
        replace with random bits using the specified integer als seed
        value for the random number generator.

        also create/update init values for flip-flops