Contributions to pyqtgraph are welcome! 

Please use the following guidelines when preparing changes:

* The preferred method for submitting changes is by github pull request
  against the "develop" branch. 

* Pull requests should include only a focused and related set of changes. 
  Mixed features and unrelated changes may be rejected.

* For major changes, it is recommended to discuss your plans on the mailing 
  list or in a github issue before putting in too much effort.

      * Along these lines, please note that pyqtgraph.opengl will be deprecated 
        soon and replaced with VisPy.

* Writing proper documentation and unit tests is highly encouraged. PyQtGraph
  uses nose / py.test style testing, so tests should usually be included in a
  tests/ directory adjacent to the relevant code. 

* Documentation is generated with sphinx; please check that docstring changes
  compile correctly.

* Style guidelines:

      * PyQtGraph prefers PEP8 for most style issues, but this is not enforced
        rigorously as long as the code is clean and readable.

      * Use `python setup.py style` to see whether your code follows
        the mandatory style guidelines checked by flake8.

      * Exception 1: All variable names should use camelCase rather than 
        underscore_separation. This is done for consistency with Qt

      * Exception 2: Function docstrings use ReStructuredText tables for 
        describing arguments:

        ```
        ============== ========================================================
        **Arguments:**
        argName1       (type) Description of argument
        argName2       (type) Description of argument. Longer descriptions must
                       be wrapped within the column guidelines defined by the
                       "====" header and footer.
        ============== ========================================================
        ```

        QObject subclasses that implement new signals should also describe 
        these in a similar table.

* Setting up a test environment.

    Tests for a module should ideally cover all code in that module,
    i.e., statement coverage should be at 100%.

    To measure the test coverage, install py.test, pytest-cov and pytest-xdist.
    Then run 'py.test --cov -n 4' to run the test suite with coverage on 4 cores.