double[] values = extractValues(attributes,elementName);
double[] values = HeatMapUtils.extractValues(attributes,elementName);
        public double computeValue(Attribute[] attributes, String elementName)            throws IllegalArgumentException        {            double[] values = extractValues(attributes,elementName);            double currentVal = 0;            for(int i=0;i<values.length;i++)            {                currentVal += values[i];            }            return currentVal/(double)values.length;        }