public function getColourByIndex($index)
    {
        if (isset($this->colourMap[$index])) {
            return $this->colourMap[$index];
        }

        return null;
    }
public function getColourByIndex($index)
    {
        if (isset($this->colourMap[$index])) {
            return $this->colourMap[$index];
        }

        return null;
    }
public function getColourByIndex ( $ index ) { if ( isset ( $ this -> colourMap [ $ index ] ) ) { return $ this -> colourMap [ $ index ] ; } return null ; }
Get colour Map Value by Position.

@param mixed $index

@return string
Get colour Map Value by Position .