Fortran77计算某段代码的CPU运行时间

      program main
      parameter(Iout=12)
      real*8 Tim0,CPUTim
      open(Iout,file='file.out')

      Tim0=CPUTim(0)  !  ini. CPU time

C     part for calc. CPU time here

      call PrtTim(Iout,Tim0)
      end



      Subroutine PrtTim(IOut,RefTim)
      Implicit Real*8(A-H,O-Z)
C
C     Print out total Time used by the job.
C
1000 Format(' Job cpu time:',I3,' days ',I2,' hours ',I2,' minutes ',
     $    F4.1,' seconds.')
C
      Time = CPUTim(0) - RefTim
      NDays = (Time / (3600.0d0*24.0d0))
      Time = Time - (NDays*(3600.0d0*24.0d0))
      NHours = (Time / 3600.0d0)
      Time = Time - (NHours*3600.0d0)
      NMin = (Time / 60.0d0)
      Time = Time - (NMin*60.0d0)
      Write(IOut,1000) NDays, NHours, NMin, Time
      Return
      End


C     2003.10.8 add for obtain CPU time
      Function CPUTim(Junk)
      Implicit Real*8(a-h,o-z)
      write(IOut, 1000) NDays, NHours, NMin, Time
      return
      end

      function CPUTim(Junk)
      implicit Real*8(a-h, o-z)
      real TimArray(2), ETime
   
      CPUTim = ETime(TimArray)
      return
      end