how to append the two graphs

[seenu87]

how to append or concat two graphs in iphone api.

ex:- (my coding)

ChartStackedColumn *pChart = [ChartStackedColumn new];
ChartLine *pChart1 = [ChartLine new];

[pChart drawWithContext: aContext dataset: pDataset chartArea: chartArea];

note:
*Pchart having stackbarchart
*pchart1 having line chart

i want to append these two graph. can anyone help in this