.. include:: operator-aliases.rst

.. testsetup:: *

   import rx


.. currentmodule:: rx

.. _operator-header-buffer:
.. _operator-header-buffer_with_count:
.. _operator-header-buffer_with_time:
.. _operator-header-buffer_with_time_or_count:
.. _operator-header-pairwise:


Buffer
======

.. seealso::

   - Official ReactiveX documentation:
     `Buffer <http://reactivex.io/documentation/operators/buffer.html>`_



.. _operator-buffer:

.. automethod:: Observable.buffer

   
   .. image:: /img/reactivex/operators/buffer1.py.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer2.py.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer3.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer4.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer5.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer5.s.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer6.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer6.s.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer7.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer7.s.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer8.py.png
      :align: center
   


.. _operator-buffer_with_count:

.. automethod:: Observable.buffer_with_count

   .. image:: /img/reactivex/operators/buffer_with_count3.py.png
      :align: center
   
   >>> import rx
   >>> items = ['red', 'yellow', 'green', 'cyan', 'blue', 'purple']
   >>> source = rx.Observable.from_(items).buffer_with_count(3);
   >>> subscription = source.subscribe(
   ...     lambda value: print("Next:", value),
   ...     lambda error: print("Error:", error),
   ...     lambda: print("Complete!")
   Next: ['red', 'yellow', 'green']
   Next: ['cyan', 'blue', 'purple']
   Complete!

   
   .. image:: /img/reactivex/operators/buffer_with_count4.py.png
      :align: center

   >>> import rx
   >>> items = ['red', 'yellow', 'green', 'cyan', 'blue', 'purple']
   >>> source = rx.Observable.from_(items).buffer_with_count(2, skip=3);
   >>> subscription = source.subscribe(
   ...     lambda value: print("Next:", value),
   ...     lambda error: print("Error:", error),
   ...     lambda: print("Complete!")
   Next: ['red', 'yellow']
   Next: ['cyan', 'blue']
   Complete!
   

.. _operator-buffer_with_time:

.. automethod:: Observable.buffer_with_time

   
   .. image:: /img/reactivex/operators/bufferWithTime5.png
      :align: center
   
   .. image:: /img/reactivex/operators/bufferWithTime7.png
      :align: center
   
   .. image:: /img/reactivex/operators/buffer_with_time5.py.png
      :align: center

   >>> import rx
   >>> ryg = ['red', 'yellow', 'green']
   >>> cbp = ['cyan', 'blue', 'purple']
   >>> xs = rx.Observable.timer(10, 50).take(3).map(lambda i: ryg[i])
   >>> ys = rx.Observable.timer(60, 50).take(3).map(lambda i: cbp[i])        
   >>> source = xs.concat(ys).buffer_with_time(timespan=100)
   >>> subscription = source.subscribe(
   ...     lambda value: print("Next:", value),
   ...     lambda error: print("Error:", error),
   ...     lambda: print("Complete!")
   Next: ['red', 'yellow']
   Next: ['green', 'cyan']
   Next: ['blue', 'purple']
   Complete!
   
   .. image:: /img/reactivex/operators/buffer_with_time7.py.png
      :align: center
  
   >>> import rx
   >>> rygc = ['red', 'yellow', 'green', 'cyan']
   >>> bp = ['blue', 'purple']
   >>> xs = rx.Observable.timer(30, 50).take(4).map(lambda i: rygc[i])
   >>> ys = rx.Observable.timer(80, 50).take(2).map(lambda i: bp[i])        
   >>> source = xs.concat(ys).buffer_with_time(timeshift=110, timespan=60)
   >>> subscription = source.subscribe(
   ...     lambda value: print("Next:", value),
   ...     lambda error: print("Error:", error),
   ...     lambda: print("Complete!")
   Next: ['red']
   Next: ['green', 'cyan']
   Next: ['blue']
   Complete!


.. _operator-buffer_with_time_or_count:

.. automethod:: Observable.buffer_with_time_or_count

   .. image:: /img/reactivex/operators/buffer_with_time_or_count6.py.png
      :align: center
   
   >>> import rx
   >>> from rx.core import Scheduler
   >>> ryg = ['red', 'yellow', 'green']
   >>> cbp = ['cyan', 'blue', 'purple']
   >>> xs = rx.Observable.timer(10, 20).take(3).map(lambda i: ryg[i])
   >>> ys = rx.Observable.timer(40, 30).take(3).map(lambda i: cbp[i])        
   >>> source = xs.concat(ys) \
   ...     .buffer_with_time_or_count(timespan=40,
   ...                                count=2,
   ...                                scheduler=Scheduler.timeout)
   >>> subscription = source.subscribe(
   ...     lambda value: print("Next:", value),
   ...     lambda error: print("Error:", error),
   ...     lambda: print("Complete!")
   Next: ['red', 'yellow']
   Next: ['green']
   Next: ['cyan', 'blue']
   Next: ['purple']
   Complete!
   

.. _operator-pairwise:

.. automethod:: Observable.pairwise