Not using strict, eh?
If you did, Perl would compain right here: 
foreach (keys %enthalpy_hash) { ...

[download]
and here 
if (exists $hash{$_})    { ...

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Since you're passing hash refs, you need to treat them accordingly;i.e, 
foreach (keys %$enthalpy_hash) { ...

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and 
if (exists $hash->{$_})    { ...

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Those are just a couple of examples, of course. There's a few other places where you used hash refs improperly.

Time to read perlref. :)

--perlplexer

In reply to Re: subroutines - passing hashes by reference by perlplexer
in thread subroutines - passing hashes by reference by Anonymous Monk

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