C
C     ..................................................................
C
C        SUBROUTINE QL9
C
C        PURPOSE
C           TO COMPUTE INTEGRAL(EXP(-X)*FCT(X), SUMMED OVER X FROM 0
C                               TO INFINITY).
C
C        USAGE
C           CALL QL9 (FCT,Y)
C           PARAMETER FCT REQUIRES AN EXTERNAL STATEMENT
C
C        DESCRIPTION OF PARAMETERS
C           FCT    - THE NAME OF AN EXTERNAL FUNCTION SUBPROGRAM USED.
C           Y      - THE RESULTING INTEGRAL VALUE.
C
C        REMARKS
C           NONE
C
C        SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED
C           THE EXTERNAL FUNCTION SUBPROGRAM FCT(X) MUST BE FURNISHED
C           BY THE USER.
C
C        METHOD
C           EVALUATION IS DONE BY MEANS OF 9-POINT GAUSSIAN-LAGUERRE
C           QUADRATURE FORMULA, WHICH INTEGRATES EXACTLY WHENEVER
C           FCT(X) IS A POLYNOMIAL UP TO DEGREE 17.
C           FOR REFERENCE, SEE
C           V.I.KRYLOV, APPROXIMATE CALCULATION OF INTEGRALS,
C           MACMILLAN, NEW YORK/LONDON, 1962, PP.130-132 AND 347-352.
C
C     ..................................................................
C
      SUBROUTINE QL9(FCT,Y)
C
C
      X=26.37407
      Y=.3290874E-10*FCT(X)
      X=18.83360
      Y=Y+.4110769E-7*FCT(X)
      X=13.46624
      Y=Y+.6592123E-5*FCT(X)
      X=9.372985
      Y=Y+.3052498E-3*FCT(X)
      X=6.204957
      Y=Y+.005599627*FCT(X)
      X=3.783474
      Y=Y+.04746056*FCT(X)
      X=2.005135
      Y=Y+.1992875*FCT(X)
      X=.8072200
      Y=Y+.4112140*FCT(X)
      X=.1523222
      Y=Y+.3361264*FCT(X)
      RETURN
      END
