| Interface | Description | 
|---|---|
| History | 
 Interface for an object that keeps track of x and y values and return
 their history when asked. 
 | 
| Class | Description | 
|---|---|
| HistoryCollapsing | 
 History that records a number of values. 
 | 
| HistoryCollapsingAverage | 
 History that records a number of values. 
 | 
| HistoryCollapsingDiscard | 
 History that records a number of values. 
 | 
| HistoryComplete | 
 History that records a data from a simulation. 
 | 
| HistoryScrolling | 
 History that records a number of values, with new ones replacing the
 earliest ones when the record is full. 
 |