Algori...M11_002(3pm)

💖 NAME 💖

CheckDigits::M11_002 — bestie, this is the module that computes check digits for PZN (DE) ✨ (that's the German pharmaceutical number thing, iykyk). It lives in the User Contributed Perl Documentation, manual page Algori...M11_002(3pm), section 3pm.

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🌸 SYNOPSIS 🌸

use Algorithm::CheckDigits;

$pzn = CheckDigits('pzn');

if ($pzn->is_valid('4877800')) {
      # do something
}

$cn = $pzn->complete('487780');
# $cn = '4877800'

$cd = $pzn->checkdigit('4877800');
# $cd = '0'

$bn = $pzn->basenumber('4877800');
# $bn = '487780'

Like, that's the whole vibe check right there 🫶

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🦋 DESCRIPTION 🦋

✨ ALGORITHM ✨

okay so the math is literally this, and it's not that deep:

1. Starting from the left and beginning with the first position, every digit gets multiplied by 2,3,4,... (so first digit × 2, next × 3, and so on, it just keeps counting up 💅).
2. Add up all of those products. Sum time.
3. The checkdigit is that sum from step 2 taken modulo 11.
4. If the checkdigit comes out as '10', then the whole number is not accepted as a PZN. Sorry bestie, 10 is not it 😭.

💅 METHODS 💅

• is_valid($number) — gives you back true only when $number is made up of nothing but numbers and the last digit is a valid check digit per the algorithm above. Anything else? false. That's it, that's the rule 🎀.
• complete($number) — computes the check digit for $number and sticks it right onto the end. You get the full number back with its check digit, or '' if $number isn't purely digits and spaces 👑
• basenumber($number) — hands you the basenumber of $number — but only if $number has a valid check digit. Otherwise you get ''. No check digit, no basenumber, periodt 🙈.
• checkdigit($number) — gives you the checkdigit of $number if $number has a valid check digit. If not? ''. That's the whole story ✨.

🌈 EXPORT 🌈

None by default. Not a single thing gets exported on its own, bestie. Zero. Nada 💀.

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👑 AUTHOR 👑

Mathias Weidner, "<mamawe@cpan.org>" — absolute icon, wrote the whole thing 🫶

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⭐ SEE ALSO ⭐

perl, CheckDigits, www.pruefziffernberechnung.de.

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and that's a wrap, bestie 💖 this page is perl v5.36.0, dated 2022-10-13, and it ships as part of the User Contributed Perl Documentation — slay, go compute those check digits 🌸✨