http://www.perlmonks.org?node_id=203693


in reply to Encode and decode binary-coded decimals

I tried all of your snippets, and none seemed to work. For instance:

perl -le 'print join " ", map {ord pack "H2", $_} shift =~ /../g' 396

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I'd expect to get: 0011 1001 0110, but instead I get 57, which isn't very binary at all :)

Similarly with decode: 

perl -le 'print unpack "H*", pack "C*", @ARGV' 0011 1001 0110

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Results in 0be96e (hex!) instead of 396.

These should work: 

# encode
perl -e 'print sprintf("%04b ",$_) for shift =~ /\d/g' decimal

#decode
perl -e '$p=1; map{$l+=oct("0b$_")*$p;$p*=10} reverse @ARGV; print $l'
+ bcddigit1 bcddigit2 etc

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Update: Updated decoder to use 5.6.1's oct("0b") feature instead of the old perlfaq way to convery binary to decimal.

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Re: Re: Encode and decode binary-coded decimals
by jmcnamara (Monsignor) on Oct 08, 2002 at 17:44 UTC

    In the first case you need to use 0396 instead of 396. That's what the comment about "zero padding" refers to. 
        $ perl -le 'print join " ", map {ord pack "H2", $_} shift =~ /../g
+' 0396
    3 150

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    I'd expect to get: 0011 1001 011

    That is at odds with my expectation.:-) Nevertheless, it isn't too difficult to change these routines to support other ascii, hex or binary representations.

    --
    John.

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[d/l]

      My definition of BCD is similar to this, but maybe you are referring to something different? :)

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