cmp does a string comparison. <=> does a numerical comparison. I could give a bit more help if I saw more of your code, since some if it is confusing me. For instance, this: 
sort { keys %{$event_hash{$key}{$b}} cmp keys %{$event_hash{$key}{$a}}
+ } keys %event_hash;

[download]
will sort based on the number of keys in the subhashes, not their value. (or so I think, since output of keys will be cast scalar by the cmp operator, yes?)

In reply to Re: Numerical sorting issues with a hash of hashes by Kageneko
in thread Numerical sorting issues with a hash of hashes by Anonymous Monk

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