#!/usr/bin/env bash

# @(#) s1       Demonstrate sort headers, carrying data fields, datamash, msort

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
# export PATH="/usr/local/bin:/usr/bin:/bin"
LC_ALL=C ; LANG=C ; export LC_ALL LANG
pe() { for _i;do printf "%s" "$_i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
em() { pe "$*" >&2 ; }
db() { ( printf " db, ";for _i;do printf "%s" "$_i";done;printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && $C dixf datamash msort

FILE=${1-data1}
E=expected-output.txt

pl " Input data file $FILE:"
head $FILE

pl " Expected output:"
head $E

# See f3 and f2 for intermediate output.
pl " Results:"
datamash -t ';' transpose < $FILE |
tee f3 |
msort -q -l -n 1,1 -d ';' --comparison-type hybrid |
tee f2 |
datamash -t ';' transpose |
tee f1

pl " Verify results if possible:"
C=$HOME/bin/pass-fail
[ -f $C ] && $C || ( pe; pe " Results cannot be verified." ) >&2

pl " Some detail for datamash, msort:"
dixf datamash msort

exit 0

$ ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 3.16.0-4-amd64, x86_64
Distribution        : Debian 8.8 (jessie) 
bash GNU bash 4.3.30
dixf (local) 1.50
datamash (GNU datamash) 1.0.6
msort 8.53

-----
 Input data file data1:
a_13;a_2;a_1;a_10
13;2;1;10

-----
 Expected output:
a_1;a_2;a_10;a_13
1;2;10;13

-----
 Results:
a_1;a_2;a_10;a_13
1;2;10;13

-----
 Verify results if possible:

-----
 Comparison of 2 created lines with 2 lines of desired results:
 Succeeded -- files (computed) f1 and (standard) expected-output.txt have same content.

-----
 Some detail for datamash, msort:

datamash        command-line calculations (man)
Path    : /usr/bin/datamash
Version : 1.0.6
Type    : ELF 64-bit LSB executable, x86-64, version 1 (SYSV ...)
Help    : probably available with -h,--help
Repo    : Debian 8.8 (jessie) 
Home    : https://savannah.gnu.org/projects/datamash/ (pm)

msort   sort records in complex ways (man)
Path    : /usr/bin/msort
Version : 8.53
Type    : ELF 64-bit LSB executable, x86-64, version 1 (SYSV ...)
Repo    : Debian 8.8 (jessie) 
Home    : http://www.billposer.org/Software/msort.html (pm)