[文件读写] 求数据处理代码，谢谢！

Program Fcode
  Implicit None
  Character(len=512) :: cStr
  integer :: k
  Open(12,File="Shielding Material Handbook.dat")
  Open(21,File="文档1")
  Open(22,File="文档2")
  Open(23,File="文档3")
  Do
    Read(12,"(a512)",ioStat=k) cStr
    if(k/=0) exit
    If( cStr(1:7) == "Density" ) then
      k = index(cStr,"=")
      if(k>3) write(21,*) trim(adjustl(cStr(k+1:)))
    ElseIf( cStr(1:8) == "Neutrons" ) then
      call PutRows(12,22)
    ElseIf( cStr(1:7) == "Photons" ) then
      call PutRows(12,23)
    End If
  End Do
  Close(12)
  Close(21)
  Close(22)
  Close(23)
contains

  Subroutine PutRows(fuIn,fuOut)
    integer :: fuIn , fuOut , j , k
    real :: r
    Do
      read(fuIn,*,ioStat=k) j , r
      if(k/=0) then
        backspace(fuIn)
        return
      end if
      write(fuOut,*) j , r
    End Do
  End Subroutine PutRows
  
End Program Fcode