pyhigamm.f

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C*********************************************************************  
    
      FUNCTION pyhigamm(X)    
    
C...Gives ordinary Gamma function Gamma(x) for positive, real arguments;    
C...see M. Abramowitz, I. A. Stegun: Handbook of Mathematical Functions 
C...(Dover, 1965) 6.1.36.   
      dimension b(8)    
      DATA b/-0.577191652,0.988205891,-0.897056937,0.918206857, 
     &-0.756704078,0.482199394,-0.193527818,0.035868343/    
    
      nx=int(x) 
      dx=x-nx   
    
      pyhigamm=1. 
      DO 100 i=1,8  
  100 pyhigamm=pyhigamm+b(i)*dx**i  
      IF(x.LT.1.) THEN  
        pyhigamm=pyhigamm/x 
      ELSE  
        DO 110 ix=1,nx-1    
  110   pyhigamm=(x-ix)*pyhigamm    
      ENDIF 
    
      RETURN    
      END