Once I tried to come up with a solution to mark some stuff (on a HTML page) with dynamic values from red to green based on these values. The positive values green and the negative ones red.

Today I stumbled over this piece of code again. I thought it might be optimizable and did some benchmarking. After I found nothing else to optimize in this snippet (suggestions?), I decided to post it. Maybe, someone will some day need a piece of code like this, too.
sub calcColor ($$$)
{
  my ($min, $max, $value) = @_;        # min = the minimal (possible) 
+value
                                       # max = the maximal (possible) 
+value
                                       # value = the value you want a 
+color for
  my $color;                           # be strict
  my $all = ($value < 0 ? $min : $max);# calculate with minimal or max
+imal value
  $all || return 'FFFF00';             # avoid divisions by zero
  $color = sprintf('%.2X', 255 - int($value/$all*255)); #calculate and
+ make hex
  return ($value < 0                   # return
    ? 'FF'.$color.'00'                 # either a red
    : $color.'FF00'                    # or a green
  );
}

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In reply to Relative color generation by NearO

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