_chart_adjust_resolution calculation

Hi,

I think that the _chart_adjust_resolution is incorrect because it doesn't consider the minimum value. Essentially, the aim is to turn each value ($v) into a percentage (0-100) so that the min $v = 0 and max $v = 100.

Therefore the algorithm should be:

newValue = (( value - min) / (max - min)) * 100

To get this to work I made the following changes:

1) make a new function : _chart_get_min()
2) correct _chart_get_max() so that the initial value is 0 and not 1 (otherwise doesn't work with graphs with values <1
3) Modify _chart_adjust_resolution

My code fragements are as shown, but to be honest this isn't tested or cleaned up at the moment because I'm not sure of all the ins & outs of the code:

/**
 * Return the min value of a single level array.
 */
function _chart_get_min($array) {
  rsort($array, SORT_NUMERIC);
  $min = is_array($array[count($array)-1]) ? 0 : $array[count($array)-1];

  if (count($array)){
    foreach($array AS $k => $v){
      if (is_array($v)){
        rsort($v, SORT_NUMERIC);
        if ($v[count($v)-1] < $min){
          $min= $v[v];
        }
      }
    }
  }

  return $min;
}

/**
 * Return the max value of a single level array.
 */
function _chart_get_max($array) {
  rsort($array, SORT_NUMERIC);
  $max = is_array($array[0]) ? 0 : $array[0];

  if (count($array)){
    foreach($array AS $k => $v){
      if (is_array($v)){
        rsort($v, SORT_NUMERIC);
        if ($v[0] > $max){
          $max = $v[0];
        }
      }
    }
  }

  return $max;
}

function _chart_adjust_resolution($chart_id, &$data, $max_value = NULL) {
  static $max;
  static $min;

  if (count($data)){
    // Set max data value
    if (!isset($max[$chart_id])){
      $max[$chart_id] = isset($max_value) ? $max_value : _chart_get_max($data);
    }

    // Set min data value
    $min[$chart_id] = _chart_get_min($data);    
    
    // Encoding resolution
    $resoluton = 100;

    // When the max is larger than the resolution
    // we need to scale down the values
    if ($max[$chart_id] > $resoluton){
      $divider = round($max[$chart_id] / $resoluton, 1);
    }
    else {
      $multiplier = round($resoluton / $max[$chart_id], 1);
    }

    foreach($data AS $k => $v){
      if (is_array($v)){
        _chart_adjust_resolution($chart_id, $data[$k]);
      }
      else {
        if (is_numeric($v)){
          // Adjust values
          $new = 0.00;
          $new = floor(( ($v - $min[$chart_id]) / ($max[$chart_id] - $min[$chart_id] ) ) * 100.00);
          $data[$k] = $new;

        }
      }
    }
  }
}

Can this be checked and updated in the release?

thanks
Rich

p.s. for some reason I have to set adjust_resolution or the graph doesn't display. Maybe there is a bug somewhere else? I'll keep looking