Just put the functions in a package and call them dynamically e.g 
{
  package My::Maths;

  sub power { return exp( $_[0] ) }
  sub log2  { return log( $_[0] )/log(2.0) }
  sub loge  { return log( $_[0] ) }
  sub log10 { return log( $_[0] )/log(10.0) }
  sub round {
          my $n = shift;
          return int($n + 0.5) if ($n >= 0);
          return int($n - 0.5);
  }
  sub trunc { return int($_[0]) }
  sub f1    { return sprintf "%.1f", $_[0] }
  sub f2    { return sprintf "%.2f", $_[0] }
  sub f3    { return sprintf "%.3f", $_[0] }
  sub f4    { return sprintf "%.4f", $_[0] }
  sub f5    { return sprintf "%.5f", $_[0] }
}

my $name = shift
  or die "Usage: $0 FUNC\n";

die "$0: unknown function method\n"
  unless my $func = My::Maths->can($method);
 
while (<STDIN> ) {
        chomp;
        my @in = split;
        print shift(@in), " ";
        print join(" ", map &$func($_), @in), "\n";
}

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HTH

_________
broquaint

In reply to Re: Dynamic function chains? by broquaint
in thread Dynamic function chains? by keymon

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