anchor.diff:             QM=17.0+3.1*SQRT(Q)-.126*Q+.0037*SQRT(Q)*Q
           ENDIF
           KM=INT(QM+0.5*M)
  +        IF(KM.GT.251) THEN
  +           F1R=DNAN()
  +           D1R=DNAN()
  +           F2R=DNAN()
  +           D2R=DNAN()
  +           RETURN
  +        END IF
           CALL FCOEF(KD,M,Q,A,FG)
           IC=INT(M/2)+1
           IF (KD.EQ.4) IC=M/2
  
positive.code:            QM=17.0+3.1*SQRT(Q)-.126*Q+.0037*SQRT(Q)*Q
          ENDIF
          KM=INT(QM+0.5*M)
          IF (Q.EQ.0.0D0) THEN
             DO 10 K=1,KM
  10            FC(K)=0.0D0
  
negative.code: C
  C      Changed GAMMA to GAMMA2 and PSI to PSI_SPEC to avoid potential conflicts.
  C
  
          FUNCTION DNAN()
          DOUBLE PRECISION DNAN
          DNAN = 0.0D0
          DNAN = 0.0D0/DNAN
          END
  
          SUBROUTINE CPDSA(N,Z,CDN)
  C
  