ADAS Subroutine agiidw

       FUNCTION AGIIDW(VVE,V,N,L,L1,LP,ISP,LT,LT1,IS,IRESOL)
       IMPLICIT REAL*8(A-H,O-Z)
C ----------------------------------------------------------------------
C
C  VERSION OF GIIDW FOR USE BY APHOTDW CALLED BY ADASRRC
C  ******************** H.P.SUMMERS, JET   30 JUNE 1992 ***************
C
C  PURPOSE: CALCULATES BOUND-FREE G-FACTORS USING DISTORTED WAVES,
C  BURGESS-SEATON PEACH OR HYDROGENIC APPROXIMATIONS
C
C  ******************** H.P.SUMMERS, JET   19 AUG. 1984 ***************
C  MAY SELECT DISTORTED WAVE MATRIX ELEMENTS, FROM PEACH TABLES, FROM
C  ORIGINAL BURGESS-SEATON APPROXIMATION OR HYDROGENIC MATRIX ELEMENTS
C  USING SELECTOR IBSOPT IN THE /BSPARS/ COMMON BLOCK.
C  FOR COMPLETENESS, THE UNRESOLVED, BUNDLED N, GBF (BURGESS AND SUMMERS
C  ,1976) CAN ALSO BE OBTAINED.
C  THE DRIVING PROGRAM MUST SET COMMON BLOCKS /PCHGTB/ AND /PCHXTB/ FOR
C  USE BY FUNCTIONS PCHG AND PCHX AND SET IFIRST=IGONE=1 AT START UP.
C  /PCHGTB/ DATA IS REQUIRED FROM FILE PCHGTAB.DATA ON STREAM 13
C  /PCHXTB/ DATA IS REQUIRED FROM FILE PCHXTAB.DATA ON STREAM 14
C  INPUT
C      VVE=V**2*E WHERE E=(FREE ELECTRON ENERGY)/Z**2 (RYD)
C      V=EFFECTIVE PRINCIPAL QUANTUM NUMBER OF BOUND ELECTRON
C      N=PRINCIPAL QUANTUM NUMBER OF BOUND ELECTRON
C      L=ORBITAL QUANTUM NUMBER OF BOUND ELECTRON
C      L1=ORBITAL QUANTUM NUMBER OF FREE ELECTRON
C      ISP=2*SP+1 WHERE SP IS TOTAL SPIN OF PARENT STATE
C      LP=TOTAL ORBITAL ANGULAR MOMENTUM QUANTUM NUMBER OF PARENT STATE
C      LT=TOTAL ORBITAL ANGULAR MOMENTUM QUANTUM NUMBER OF BOUND SYSTEM
C      LT1=TOTAL ORBITAL ANGULAR MOMENTUM QUANTUM NUMBER OF FREE SYSTEM
C      IS=2*S+1 WHERE S IS TOTAL SPIN OF SYSTEM
C      IRESOL=1 GIVES GII((LP,SP)N L LT S,(LP,SP)E L1 LT1 S)
C            =2 GIVES GII((LP,SP)N L LT S,(LP,SP)E L1 S) =ABOVE LT1 SUM
C            =3 GIVES GII((LP,SP)N L S,(LP,SP)E L1 S)   = ABOVE LT SUM
C            =4 GIVES GII((LP,SP)N L,(LP,SP)E L1)      = ABOVE S SUM
C            =5 GIVES GII(N,E) = GBF  (BURGESS AND SUMMERS)
C  OUTPUT
C      AGIIDW  THE BOUND-FREE GAUNT FACTOR
C-----------------------------------------------------------------------
C  UPDATE:  01/10/96  HP SUMMERS - BYPASS PEACH DATA INPUT IF IBSOPT=3
C-----------------------------------------------------------------------
C UNIX-IDL PORT:
C
C AUTHOR:  WILLIAM OSBORN (TESSELLA SUPPORT SERVICES PLC)
C
C DATE:    4TH JULY 1996
C
C VERSION: 1.1                          DATE: 04-07-96
C MODIFIED: WILLIAM OSBORN
C               - FIRST VERSION.
C VERSION: 1.2                          DATE: 14-10-96
C MODIFIED: WILLIAM OSBORN
C               - ADDED CHANGES DATED 01/10/96 ABOVE.
C
C VERSION: 1.3                          DATE: 16-05-07
C MODIFIED: Allan Whiteford
C               - Modified comments as part of subroutine documentation
C                 procedure.
C
C-----------------------------------------------------------------------
C ----------------------------------------------------------------------
      INTEGER             IRESOL,      IS,          ISP,         L
      INTEGER             L1,          LP,          LT,          LT1
      INTEGER             N
      REAL*8              V,           VVE