                 return point.x } )
         }
         else {
-            labels = xLabels
+            labels = xLabels!
         }
         
         let scaled = scaleValuesOnXAxis(labels)

    The values to display as labels on the x-axis. You can format these values with the `xLabelFormatter` attribute.
    As default, it will display the values of the series which has the most data.
    */
    var xLabels: Array<Float>!
    
    /**
    Formatter for the labels on the x-axis. The `index` represents the `xLabels` index, `value` its value:

            }
        }
        else {
            labels = yLabels!
        }
        
        let scaled = scaleValuesOnYAxis(labels)
