Rekeying data - Perl example

More than Simple Lists and Hashes! example from a Well House Consultants training course
More on More than Simple Lists and Hashes! [link]

This example is described in the following article(s):
• Transforming data in Perl using lists of lists and hashes of hashes - [link]

Source code: ar3 Module: P217

# Convert a file of people, with the skills of each ...
# ... to a report of skills, with a list of the people with each

while (<DATA>) {
        ($name,@skills) = split;
        last if (/DONE/);
        foreach $sk(@skills) {
                push @{$sktab{$sk}},$name;
                }
        }

foreach $sk(sort (keys (%sktab))) {
        print "Skill: $sk\n";
        @peeps = sort(@{$sktab{$sk}});
        print "Practitioners: @peeps\n\n";
        }

# For ease of demonstration, data is below not in a separate file
# And we have added a DONE at which the program stops reading.

__END__
antonia Perl XML PHP Knitting MySQL
barbara Tcl/Tk Lua Ruby Java
cherry Perl Java Ruby MySQL
delia XML PHP Java Lua
ethel MySQL Perl Tcl/Tk Lua
florence Javascript Ruby Lua PHP Java
gloria XML Perl Tcl/Tk MySQL
hazel PHP Python Perl Ruby Lua
iris Perl MySQL Tcl/Tk
jenny XML Perl Ruby Lua
kerry ASP Tcl/Tk Ruby MySQL
leane PHP Python Lua Perl Java
margaret XML Ruby MySQL Tcl/Tk
nina Tcl/Tk Perl Lua Ruby PHP
olivia MySQL Python Lua PHP
petra XML Tcl/Tk Lua Perl Ruby
queenie Lua Ruby Perl MySQL
rita PHP Lua Ruby Perl
sally Tcl/Tk Perl XML MySQL
tina Tcl/Tk Ruby Java
uva MySQL Perl Java PHP
venus Java Perl Ruby Lua
wendy Perl Tcl/Tk Lua MySQL
xena Java Perl PHP Lua XML
yollanda Ruby MySQL Tcl/Tk
zoe Ruby Lua Perl PHP
adam Python Tcl/Tk Perl MySQL
alex MySQL Ruby PHP
barry Python XML Java Perl PHP
charles Perl Ruby MySQL Tcl/Tk
david Perl Tcl/Tk Java
ed Ruby Perl Java PHP
fred MySQL Perl Java XML
graham Lua Perl Tcl/Tk
harry PHP Python Java
ivan Ruby Java Perl Tcl/Tk MySQL
john PHP XML Java Perl
ken Tcl/Tk Python Java Perl
len Perl Java MySQL Ruby
morris Perl Java PHP Tcl/Tk
nigel PHP Python Java Perl
orpheus MySQL Ruby Tcl/Tk XML
peter PHP Java Perl
quentin Tcl/Tk Perl PHP Ruby
rupert Java Python MySQL
steve Tcl/Tk Perl PHP Ruby
tommy Perl Java XML
ulsyees Java PHP Perl
victor Ruby Perl Tcl/Tk MySQL
william Ruby Perl PHP
xavier PHP Java Perl
yuri XML PHP Perl Tcl/Tk
zachary MySQL Java Tcl/Tk

DONE

# Here is what the output looks like:

Skill: ASP
Practitioners: kerry

Skill: Java
Practitioners: barbara barry cherry david delia ed florence fred harry ivan john ken leane len morris nigel peter rupert tina tommy ulsyees uva venus xavier xena zachary

Skill: Javascript
Practitioners: florence

Skill: Knitting
Practitioners: antonia

Skill: Lua
Practitioners: barbara delia ethel florence graham hazel jenny leane nina olivia petra queenie rita venus wendy xena zoe

Skill: MySQL
Practitioners: adam alex antonia charles cherry ethel fred gloria iris ivan kerry len margaret olivia orpheus queenie rupert sally uva victor wendy yollanda zachary

Skill: PHP
Practitioners: alex antonia barry delia ed florence harry hazel john leane morris nigel nina olivia peter quentin rita steve ulsyees uva william xavier xena yuri zoe

Skill: Perl
Practitioners: adam antonia barry charles cherry david ed ethel fred gloria graham hazel iris ivan jenny john ken leane len morris nigel nina peter petra queenie quentin rita sally steve tommy ulsyees uva venus victor wendy william xavier xena yuri zoe

Skill: Python
Practitioners: adam barry harry hazel ken leane nigel olivia rupert

Skill: Ruby
Practitioners: alex barbara charles cherry ed florence hazel ivan jenny kerry len margaret nina orpheus petra queenie quentin rita steve tina venus victor william yollanda zoe

Skill: Tcl/Tk
Practitioners: adam barbara charles david ethel gloria graham iris ivan ken kerry margaret morris nina orpheus petra quentin sally steve tina victor wendy yollanda yuri zachary

Skill: XML
Practitioners: antonia barry delia fred gloria jenny john margaret orpheus petra sally tommy xena yuri

Learn about this subject

This module and example are covered on the following public courses:
* Perl Programming
* Perl for Larger Projects
* Perl bootcamp
* Learning to program in Perl
* Perl Programming
Also available on on site courses for larger groups

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Other Examples

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