| :orphan: |
|
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| .. _numpy-compatibility: |
|
|
| NumPy compatibility |
| ******************* |
|
|
| NumPy_ forms an essential basis for astropy, and astropy's development has led |
| to the identification of problems with some of numpy's functionality. Often, |
| these are corrected in later versions of numpy, but in order for astropy not |
| to depend on these, work-arounds are made, usually in the code. If functions |
| are used in more than one place, however, it can be more convenient to provide |
| patched routines. Hence, `astropy.utils.compat.numpy`. |
|
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|
|
| Adding a patched routine |
| ======================== |
|
|
| To ensure that patched code is only used when required, and that it will be |
| easy to remove it if it is no longer needed for any supported version of |
| NumPy_, the following procedure should be used to add a patched routine: |
|
|
| * Copy over a correct version of the relevant numpy file to its |
| corresponding location below the ``astropy/utils/compat/numpy`` directory. |
| * In this file, remove everything that does not have to be changed. If |
| necessary, import required pieces from numpy. |
| * Define a function that tests whether or not a patched version is needed, by |
| directly testing whether the desired functionality is present. Suggested |
| function names are ``PR |
| or ``GE |
| * Place the redefinition of the relevant piece of code inside an ``if`` |
| statement that uses the function just defined. This should ensure that if a |
| sufficiently high version of numpy is used, no replacement is made. |
| * In ``numpy/__init__.py``, import your patched code. |
| * In ``numpy/tests``, add a new test routine that tests that the patch is used |
| when necessary (i.e., test the test function), and that it provides the |
| desired functionality. |
|
|
| For an example, see ``numpy/lib/stride_tricks.py`` and the corresponding |
| ``numpy/tests/test_broadcast_arrays.py``. |
|
|
| Note that patched routines will normally only be considered if they are part |
| of NumPy_. Thus, if the patch concerns a new bug discovered in numpy, a `pull |
| request <https://github.com/numpy/numpy/pulls>`__ should first be made to |
| NumPy_ (which can of course form the basis of a `pull request |
| <https://github.com/astropy/astropy/pulls>`__ to ``astropy``). |
|
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|
|
| Reference/API |
| ============= |
| .. automodapi:: astropy.utils.compat.numpy |
| :no-inheritance-diagram: |
|
|
| .. _Numpy: http://www.numpy.org/ |
|
|
