C IRIS VERSION 4/4/91 KFB
      FUNCTION QUADm(AA,BB,CC)
      REAL*8 A,B,C
      A=AA
      B=BB
      C=CC
      QUADm=-B/2./A+(.5/A*DSQRT(ABS(B*B-4*A*C)))
      IF (QUADm .GT. 0.) GO TO 10
      QUADm=0.
10    SAVE
      RETURN
      END