ADAS Subroutine pypr

       SUBROUTINE PYPR(E,E11,N,N11,EM,Z1,PHI,WI,WJ,TE,INTD,PY,RDEXC)   
C
       IMPLICIT REAL*8(A-H,O-Z)                                         
C
C-----------------------------------------------------------------------
C
C  ****************** FORTRAN77 SUBROUTINE: PYPR ***********************
C
C  PURPOSE: CALCULATES PY FACTOR (CF. VAN REGEMORTER,1962) USING
C           PERCIVAL,RICHARD AND COWORKER CROSS-SECTIONS.                                       
C
C  VALID ONLY FOR ELECTRON INDUCED TRANSITIONS BETWEEN WHOLE PRINCIPAL
C  QUANTUM SHELLS IN HYDROGEN AND HYDROGENIC IONS, FOR N,N11>4       
C  HOWEVER ADJUSTMENTS MADE TO ALLOW USE OF FORMULAE FOR N<4        
C  ********* H.P.SUMMERS, JET  12 NOVEMBER 1984  ***************   
C  INPUT                                                          
C      E=1/V**2 WITH V THE INITIAL EFFECTIVE PRINCIPAL QUANTUM NUMBER   
C      E11=1/V11**2 WITH V11 THE FINAL EFFECTIVE PRINCIPAL QUANTUM NUMBE
C      N=INITIAL PRINCIPAL QUANTUM NUMBER                              
C      N11=FINAL PRINCIPAL QUANTUM NUMBER (REQUIRE N11>N AND V11>V)   
C      EM=REDUCED MASS OF COLLIDING PARTICLE (MUST BE 1.0 IN THIS CASE)
C      Z1=TARGET ION CHARGE +1                                        
C      PHI=(IH/EIJ)F WITH EIJ=TRANSITION ENERGY, F=ABS. OSCILL. STRENGTH
C      WI=STATISTICAL WEIGHT OF INITIAL LEVEL                           
C      WJ=STATISTICAL WEIGHT OF FINAL LEVEL                            
C      TE=ELECTRON TEMPERATURE(K)                                     
C      INTD=<3 FOR TWO POINT GAUSSIAN QUADRATURE.                    
C          = 3 FOR THREE POINT GAUSSIAN QUADRATURE                  
C          =>3 FOR FOUR POINT GAUSSIAN QUADRATURE                  
C  OUTPUT                                                         
C      PY=P FACTOR                                               
C      RDEXC=DEXCITATION RATE COEFFICIENT (CM+3 SEC-1)              
C
C NOTES: THIS ROUTINE IS NOT YET PROPERLY ANNOTATED
C
C UNIX-IDL PORT:
C
C VERSION: 1.1                          DATE: 16-1-96
C MODIFIED: TIM HAMMOND (TESSELLA SUPPORT SERVICES PLC)
C               - FIRST VERSION
C
C VERSION: 1.2                          DATE: 16-05-07
C MODIFIED: Allan Whiteford
C             - Updated comments as part of subroutine documentation
C               procedure.
C
C-----------------------------------------------------------------------
C
      INTEGER             INTD,        N,           N11
      REAL*8              E,           E11,         EM,          PHI
      REAL*8              PY,          RDEXC,       TE,          WI
      REAL*8              WJ,          Z1