.. _06_exercises_a:

=========
Exercises
=========

Exercise 1
==========

#. Load the EventWorkspace *HYS_11388_event.nxs*
#. Sum across each spectra in the workspace using the **SumSpectra**
   algorithm. Set the **OutputWorkspace** to be called *Sum*
#. **Rebin** this grouped workspace, specify **OutputWorkspace** to
   *binned* and that the bin width is *100* microseconds, and keep
   **PreserveEvents** ticked
#. Right-click the workspace called *binned* and choose the **Plot
   Spectrum** option. Once the graph is plotted, leave do not delete it
#. Events in an EventWorkspace may get filtered according to other
   recorded events during the experiments. At perhaps the simplest level
   you can filter out events between specific times. Use
   :ref:`algm-FilterByTime` for this. It has a parameter called
   **StartTime**, which is the start time, in seconds, since the start
   of the run. Events before this time are filtered out. Run
   **FilterByTime** on *binned* with **StartTime**\ =\ *4000* and call the
   **OutputWorkspace** *FilteredByTime*
#. Drag the workspace FilteredByTime into the plot where workspace
   *binned* is plotted. What you should see now is:

.. figure:: /images/MBC_algorithm_example.png
   :align: center
   :width: 700px

Show the History of the *FilteredByTime* workspace, which should match the steps above.

Exercise 2
==========

#. Using the *binned* workspace from the previous example as the
   InputWorkspace, use **FilterByLogValue** with
   **LogName**\ =\ *proton_charge*, **MinimumValue**\ =\ *17600000*,
   **MaximumValue**\ =\ *17890000*
#. Overplot the OutputWorkspace over your existing plots from the
   previous example
#. Run **FilterBadPulses** with **InputWorkspace**\ =\ *binned* and
   **LowerCutoff**\ =\ *99.999*
#. Overplot the *OutputWorkspace* over your existing plots

.. figure:: /images/MBC_Alg_Example2.png
   :align: center
   :width: 700px

Exercise 3 - now you choose the OutputWorkspace names!
======================================================

#. **Load** *HYS_11388_event.nxs* as in Exercise 1, but this time perform
   the filtering as part of the Loading, by setting **FilterByTimeStart**\ =\ *4000*
#. **SumSpectra** on your new workspace
#. Use **RebinToWorkspace** to achieve the same binning as the existing
   *binned* workspace
#. Plot both your newly rebinned workspace and *FilteredByTime* created
   in exercise 1 on a new plot.

.. figure:: /images/MBC_Alg_Example3.png
   :align: center
   :width: 700px