SciTools/iris — pull request #282 by bjlittle (2012-12-18 15:25:24+00:00)
Title: Deal with netCDF non-monotonic and masked coordinates.

This PR extends the graceful loading capability of netCDF:
* Copes with non-monotonic coordinate variables.
* Copes with weak monotonic coordinate variables.
* Copes with masked coordinate variables.
* Copes with *almost* compliant CF latitude/longitude units.

As a side effect, this PR performs netCDF optimisation. The coordinate points data payload monotonic check was being performed **twice**: once by `cf.py` and a further time within the `PyKE` rules whenever a `DimCoord` is created.

The `CFCoordinateVariable` criterion has been relaxed by default to not perform the monotonic points check of a netCDF variable. This can still be turned on via a keyword to the `cf.CFReader` if so desired.