%N mpsign %F $MIR/src/subs/mp.for
%D Return the sign of a multi-precision integer.
%P rjs
%B
        integer function mpSign(v)

        implicit none
        integer v(3)

  Return the sign of a multi-precision integer.

  Input:
    v          Multi-precision integer to be considered.
  Output:
    mpSign     -1, 0 or +1 depending on whether v is negative, zero
               or positive respectively.
