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% Insert source immediately following \begin{verbatim}
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\begin{verbatim}
c-----------------------------------------------------------
c     Computes and reports estimate of machine epsilon.
c
c     Recall: machine epsilon is smallest positive 'eps' 
c     such that 
c
c             (1.0d0 + eps ) .ne. (1.0d0)
c
c     Program accepts optional argument which specifies 
c     division factor: values close to 1.0 will result 
c     in more accurate estimate of machine epsilon.
c-----------------------------------------------------------
\end{verbatim}
\newpage
\begin{verbatim}
      program         meps

      implicit        none

c-----------------------------------------------------------
c     Note use of 'r8arg', available in 'libp329f.a' which
c     works exactly like 'i4arg' except that it returns 
c     a real*8 value parsed from the specified command-line
c     argument
c-----------------------------------------------------------
      real*8          r8arg

      real*8          default_fac
      parameter     ( default_fac = 2.0d0 )

      real*8          eps,         neweps,        fac

      fac = r8arg(1,default_fac)
      write(0,*) 'meps: using division factor: ', fac

      eps    = 1.0d0
      neweps = 1.0d0
100   continue
         if( 1.0d0 .eq. (1.0d0 + neweps) ) then
            write(*,*) eps
            stop
         else
            eps    = neweps
            neweps = neweps / fac
         end if
      go to 100
200   continue

      stop

      end
\end{verbatim}
\newpage
\begin{verbatim}
############################################################
# Output from 'meps' on SGIs (IEEE 64-bit floating point)
############################################################

einstein% meps
 meps: using division factor:    2.000000000000000    
   2.2204460492503131E-16

einstein% meps 1.01
 meps: using division factor:    1.010000000000000    
   1.1104218387155329E-16

einstein: meps 1.0001
 meps: using division factor:    1.000100000000000    
   1.1102645224601785E-16
\end{verbatim}
}
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