You could trap warnings for not numerics 
use warnings;

my $days = 'oops'; 
eval {
   local $SIG{__WARN__} = sub { die "not numeric" };
   $days += 0;
};
if ($@) {
   # at this point $days will be zero
   # and $@ will be "not numeric"
}

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In reply to Re: String/Numeric Manipulation by mifflin
in thread String/Numeric Manipulation by Ms. T.

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