So the solution would be: 
#You might want to do something to look for say sin, cos, tan, etc.
unless( $str =~ /[^0-9+-*^/.,_()]/ ){
  eval($str);
}

[download]

--
perl -p -e "s/(?:\w);([st])/'\$1/mg"

In reply to Re: Re: Parsing Math Strings by belg4mit
in thread Parsing Math Strings by pokemonk

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