IGSeriesDataSource Protocol Reference
Conforms to  NSObject 
Declared in  Series.h 
Overview
The IGSeriesDataSource protocol is adopted by an object that mediates the application’s data model for an IGSeries object. The data source provides the series object with the information it needs to construct and modify a chart view.
The required methods of the protocol provide the points to be displayed by the chart view along with the total number of points in the series. There are also optional methods for creating point tooltips.
Tasks

– numberOfPointsInSeries:
Asks the data source for the total number of points in the series.
required method 
– series:pointAtIndex:
Asks the data source for an IGDataPoint to be placed at a given location.
required method 
– allPointsForSeries:
Askds the data source for all IGDataPoint objects.

– series:updatePointAtIndex:

– series:tooltipForPointAt:
Asks the data source for a tooltip that will be used for a point at a specified index.

– objectAtIndex:
Returns the original data object at a specified index.

– objectForDataPoint:inSeries:
Returns the original data object based on its corresponding data point.
Instance Methods
allPointsForSeries:
Askds the data source for all IGDataPoint objects.
 (NSArray *)allPointsForSeries:(IGSeries *)series
Parameters
 series
Series requesting the information.
Return Value
Returns an array of IGDataPoint objects.
Discussion
This method should only be implemented if your data is already in the IGDataPoint format. Otherwise you should covert your data point by point using the series:pointAtIndex: method.
Declared In
Series.h
numberOfPointsInSeries:
Asks the data source for the total number of points in the series.
 (NSInteger)numberOfPointsInSeries:(IGSeries *)series
Parameters
 series
Series requesting the information.
Return Value
Returns the number of points in the series.
Declared In
Series.h
objectAtIndex:
Returns the original data object at a specified index.
 (NSObject *)objectAtIndex:(NSInteger)index
Parameters
 index
Index of the data object to be returned.
Return Value
Returns the data object at a specified index.
Declared In
Series.h
objectForDataPoint:inSeries:
Returns the original data object based on its corresponding data point.
 (NSObject *)objectForDataPoint:(IGDataPoint *)point inSeries:(IGSeries *)series
Parameters
 point
IGDataPoint that represents the original object.
 series
IGSeries that holds the data point.
Return Value
Returns the data object that corresponds to the given data point.
Declared In
Series.h
series:pointAtIndex:
Asks the data source for an IGDataPoint to be placed at a given location.
 (IGDataPoint *)series:(IGSeries *)series pointAtIndex:(NSInteger)index
Parameters
 series
Series requesting the information.
 index
Index of the created data point.
Return Value
Returns an object inheriting IGDataPoint that will be used by the series.
Declared In
Series.h
series:tooltipForPointAt:
Asks the data source for a tooltip that will be used for a point at a specified index.
 (UIView *)series:(IGSeries *)series tooltipForPointAt:(NSInteger)index
Parameters
 series
Series requesting the information.
 index
Index of the data point, to which the tooltip will be assigned.
Return Value
Returns a view that will be used as a tooltip.
Declared In
Series.h