Handling NULL values in charts

forecasts/models.py

@@ -155,7 +155,7 @@ class ForecastResult:
                 the_value = forecast_result.all_values.get(result_parameter.getNamespaceKey(), "")
                 if the_value != "" and timeseries.get(result_parameter.getNamespaceKey(), None) != None:
                     try:
-                        data_point = [util.get_unix_timestamp(forecast_result.valid_time_start),Decimal(the_value)]
+                        data_point = [util.get_unix_timestamp(forecast_result.valid_time_start),Decimal(the_value) if the_value is not None else None]
                         timeseries[result_parameter.getNamespaceKey()]["data"].append(data_point)
                     except InvalidOperation:
                         continue