Rename DatasetArray to DataArray?

[shoyer]

This would make it less ambiguous that this is the preferred way to access and manipulate data in xray.

On a related note, I would like to make XArray more of an internal implementation detail that we only expose to advanced users.

[akleeman]

+1 I like the name DataArray much more than DatasetArray

[shoyer]

For reference, I got the name "DataArray" from this Wes McKinney blog post:
http://wesmckinney.com/blog/?p=77

I will add a pull-request with this name change, perhaps along with the focus -> name change. For now, it will include DatasetArray = DataArray to make the change backwards compatible.

It would also be nice to be create to a DataArray (including both dimensions and coordinate values) from scratch without making a Dataset first. Ideally, we could just write

DataArray(data, x=np.arange(5), y=np.arange(10))

but unfortunately Python doesn't support inferring the order of keyword arguments.

Some options (not necessarily mutually exclusive), in descending (ascending) order of their machine (human) friendliness:

DataArray(data, [('x', np.arange(5)), ('y', np.arange(10))])
DataArray(data, ['x', 'y'], [np.arange(5), np.arange(10)])
DataArray(data, 'x', np.arange(5), 'y', np.arange(10))

[shoyer]

Fixed by #73.