Transforming observables

The following operators allow us to make some transformations on the items emitted on source observables. Some of them have already been covered in the previous chapters. They are the following:

Operator	Description	Chapter
map	Maps each item to another value	1
flat_map	Maps each item to an observable and flattens all emitted items in a single observable	6

The buffer operator

The buffer operator groups items emitted on the source observable based on different types of window selectors. These selectors can be defined via another observable, an item count, or time information. The following figure shows the marble diagram of the buffer operator:

Figure 9.1: The buffer operator

This operator...