Commit: 9c8455b2e3ab9742aa0dfa59ecc501a0e8b476b4 - MESS (hg)

Commit MetaInfo

• Revisión: 9c8455b2e3ab9742aa0dfa59ecc501a0e8b476b4 (tree)
• Tiempo: 2017-10-21 04:16:33
• Autor: Albert Mietus < albert AT mietus DOT nl >
• Commiter: Albert Mietus < albert AT mietus DOT nl >

Log Message

Added dPID python 'homework' exercise in DRAFT

Cambiar Resumen

• modified: pyMESS/training/dPID/exercise.rst
• modified: pyMESS/training/dPID/index.rst

Diferencia incremental

diff -r c4c263a4f1e9 -r 9c8455b2e3ab pyMESS/training/dPID/exercise.rst
--- a/pyMESS/training/dPID/exercise.rst	Fri Oct 20 18:32:04 2017 +0200
+++ b/pyMESS/training/dPID/exercise.rst	Fri Oct 20 21:16:33 2017 +0200
@@ -4,7 +4,7 @@
 .. _dPID_exercise:
 
 ==============
-dPID: exercise
+dPID: Exercise
 ==============
 :status: pre-alpha
 
@@ -23,19 +23,61 @@
    The :class:`dpid.dPID` class is discrete; it only calculates the :meth:`dpid.dPID.result` when requested. This implies the
    (return) value of :meth:`dpid.dPID.result` will depend on when it is called (relative to the other methods).
 
-   * So, timing may be relavant in your (test)-code. One can use ``time.sleep`` to controll that. By using a floating-point
-     parameter, this is accurate in the milli-seconds range.
+   * So, timing may be relavant in your (test)-code. One can use ``time.sleep`` to controll that. Usa a floating-point
+     parameter for sub-second resolution. Typically, the function is accurate in the milli-seconds range.
 
-   * By using a (small, relavant) MARGIN when comparing values, small derivations (in e.g. timing) can be compensated.
+   * Compare using a small *MARGIN*, to allow derivations due e.g. timing. See the :ref:`examples <dPID_test_examples>`.
 
    .. seealso:: Convenient python functions
 
       * https://docs.python.org/3.5/library/time.html?highlight=sleep#time.sleep
       * https://docs.python.org/3.5/library/functions.html?highlight=abs#abs
 
+Instructions
+~~~~~~~~~~~~
+
+* Use the `pytest <https://pytest.readthedocs.io>`__ framework, to shorten tests-code.
+
+  - :ref:`pytest_into` is a summary with everything you need for this exercise.
+  - You can use :ref:`dPID_test_examples` as *template* for your own files.
+
+* Start by running ``pytest`` as shown.
+
+  - Reproduce the shown output first, before adding your own files.
+  - Remember; the output text will differ slightly; for paths, dates etc.
+
+* Add a (one) new file: ``test_<something>.py``.
+
+  - Copy the start of the file (above the first function); update the copyright.
+  - Write a single test-function:
+
+    * Create a :class:`dpid.dPID` instance with known, **simple** ``P``, ``I`` and ``D`` settings.
+    * Give it a :meth:`~dpid.dPID.setpoint` and :meth:`~dpid.dPID.measured` value.
+    * Request a :meth:`~dpid.dPID.result`.
+    * Assert the returned value is (almost) equal to the pre-computed number.
+
+* Run ``pytest`` again.
+
+  - It should run both the existing example, and the new test-file.
+  - The test should fail! As the *empty* class always returns ``0``, that is easy.
+  - Watch for *syntax errors*, and errors but AssertionError. Improve your code when needed
+
+* Repeat, either by adding test-function to that file, or adding more test-files.
+
+  - When needed, you can add auxiliary functions; just don’t use the *test*-phrase in there name.
+  - Or continue first with the implementation part. And add more test later (for other functions).
+  - Each test should be a little more complicated as the existing onces.
+  - Or better: start with the trivial once. Then the almost-trivial, etc.
+
+    * Start testing a “*P-only*” PID-controller
+    * Then an “*I-only*”, then a “*D-only*”. After which you test a simple combination
+    * etc.
+
 Code second
 -----------
 
+When a part of the functionality is tested (or at least: there is test-code for), you can start implementing
+the :class:`~dpid.dPID` class. Keep is simple. The only objective is to **make one failing test pass**.
 
 And improve (refactor)
 ----------------------

diff -r c4c263a4f1e9 -r 9c8455b2e3ab pyMESS/training/dPID/index.rst
--- a/pyMESS/training/dPID/index.rst	Fri Oct 20 18:32:04 2017 +0200
+++ b/pyMESS/training/dPID/index.rst	Fri Oct 20 21:16:33 2017 +0200
@@ -18,7 +18,7 @@
 *************
 
 .. toctree::
-
+   :maxdepth: 3
 
    class
    exercise