PROGRAM stotau 
*************************************************************************
* Conversion of sigma functions to                                 *
* frequence dependent 1/tau, m/m*                                       *
* from standard input it reads:
* input filename
* epsilon infinity, plasma-frequency
* the input file must have the format x s1 s2                       *
*************************************************************************
      REAL X(10000),s1,s2,gam,msm
      complex epsil(10000),einv
      INTEGER I,mm
      mm=10000
      do 10 i=1,mm                                                  
       READ(*,*,END=11) X(i),s1,s2
       epsil(i)=cmplx(s1,s2)*(0.,1.)/(x(i)*0.5*0.0333795) 
10    continue   
11    mm=i-1
      do 25 i=1,mm
       einv=1./epsil(i)
       gam=-aimag(einv)/x(i)
       msm=-real(einv)/(x(i)*x(i))
       write(*,*) x(i),gam,msm
25    continue
      END