Bsrgvty

Is it possible to sort between two strings in a large file ?

e.g.
Current file is as:

 0cf Front Brake
 0d0 Rear Brake
 0ce Handle Bars
HUT 03 VR Controls
 009 Vest
 001 Belt
 002 Body Suit
 020 Stereo Enable
 003 Flexor
 007 Hand Tracker
 004 Glove
 006 Head Mounted Display
 008 Oculometer
 00a Animatronic Device
 000 Unidentified
 021 Display Enable
 005 Head Tracker
HUT 04 Sport Controls
 000 Unidentified
 002 Golf Club
 001 Baseball Bat

And the desired output is as:

 0ce Handle Bars
 0cf Front Brake
 0d0 Rear Brake
HUT 03 VR Controls
 000 Unidentified
 001 Belt
 002 Body Suit
 003 Flexor
 004 Glove
 005 Head Tracker
 006 Head Mounted Display
 007 Hand Tracker
 008 Oculometer
 009 Vest
 00a Animatronic Device
 020 Stereo Enable
 021 Display Enable
HUT 04 Sport Controls
 000 Unidentified
 001 Baseball Bat
 002 Golf Club

Here, Section HUT 03 VR Controls and HUT 04 Sports Controls is sorted out.

In given file, Section headers starts with non-space characters while section content always begins with space or tab. Since this file have 100+ sections then it will not be feasible to hard-code section name in script/command

In Python:

#!/usr/bin/python3

with open("file.txt", "r") as ins:
 lines = []
 for line in ins:
 if line.startswith((" ", "t")):
 lines.append(line)
 else:
 lines.sort()
 print(*lines, end = "", sep = "")
 print(line, end = "")
 lines = []
 lines.sort()
 print(*lines, end = "", sep = "")

This sorts all the sections (separately), not only those between two specific lines.

For the fun, here is a way to sort a single section using ex:

ex file <<%
/HUT
+1,/HUT/-1!sort
w file.sorted
q
%

$ awk 'BEGIN OFS="t"; s=0 /^[^[:blank:]]/ print ++s "b", $0; next print s, $0 ' file | sort -n | cut -f 2-
 0ce Handle Bars
 0cf Front Brake
 0d0 Rear Brake
HUT 03 VR Controls
 000 Unidentified
 001 Belt
 002 Body Suit
 003 Flexor
 004 Glove
 005 Head Tracker
 006 Head Mounted Display
 007 Hand Tracker
 008 Oculometer
 009 Vest
 00a Animatronic Device
 020 Stereo Enable
 021 Display Enable
HUT 04 Sport Controls
 000 Unidentified
 001 Baseball Bat
 002 Golf Club

This uses awk to add a number (and a tab separator) in front of each line corresponding to the section that this line is in. For section headers, we add a number followed by a backspace character (only because backspace sorts before tabs). Then we simply sort the resulting data on these numbers before removing them and the added tab separators.

Section headers are detected by looking for non-blank characters at the start of the line.

You could get awk and sort to cooperate to get the job done.

awk '
 /^[[:blank:]]/print 
 close("sort"); print; 
 ENDclose("sort")
' file

• Pipe each content line into sort
  


• Call close on sort when a section marker is encountered; this causes sort to flush its output to standard output and exit


• Print the section marker


• A new instance of sort takes over for the content lines following the section marker


• Call close on sort at the end to take care of trailing content

For such tasks I often find it tedious to write a script. If it only needs to be done once and maybe for a few files, it can be done quite nicely using a macro if you open the file in vim and type:

• 
  GoFAKE SECTION<ESC>: add a fake section in the end, and make sure this is at the start of the line (you may have cindent or autoindent enabled). This is required for sorting the last section as well.


• 
  gg: back go to the start of the file, then the file starts with a section go down one line with j
  


• 
  qq: start recording a macro to register q


• 
  v: start selection


• 
  /^S+<Enter>: search for the start of the next section


• 
  k: up one line


• 
  :!sort<Enter: sort the section


• 
  nj: go to the first element of the next section


• 
  q: stop recording the macro


• 
  @q: repeat the macro


• 
  100@@: repeat the macro a few times (until no sections left)


• 
  dd: delete the last line of the file (the FAKE SECTION)

You may want to :set lazyredraw to speed up macro execution.