在Python中导入类似Excel的文本：自动解析固定宽度的列

set fh [open ex.txt]
set contents [read $fh];#ok for small-to-medium files.
close $fh

#first pass
set occupied {}
set lines [split $contents \\n];#split contents at line breaks.
foreach line $lines {
  set chrs [split $line {}];#split each line into chars.
  set pos 0
  foreach chr $chrs {
    if {$chr ne \" \"} {
      lappend occupied $pos
    }
    incr pos
  }
}

#drop out with long list of occupied \"positions\": sort to create
#our sieve.
set datacols [lsort -unique -integer $occupied]
puts \"occupied: $datacols\"

#identify column boundaries.
set colset {}
set start [lindex $datacols 0];#first occupied pos might be > 0??
foreach index $datacols {
  if {$start < $index} {
    set end $index;incr end -1
    lappend colset [list $start $end]
    puts \"col break starts at $start, ends at $end\";#some instro!
    set start $index
  }
  incr start
}

#Now convert input file to trivial case output file, replacing
#sieved space chars with tab characters.
set tesloc [lreverse $colset];#reverse the column list!
set fh [open ex_.txt w]
foreach line $lines {
  foreach ele $tesloc {
    set line [string replace $line [lindex $ele 0] [lindex $ele 1] \"\\t\" ]
  }
  puts \"newline is $line\"
  puts $fh $line
}
close $fh