Python 3 support + simplification course

The main point of the release is to support python3.

Along this way, the dimarray.geo package was removed, as will be all non-essential components in future releases.
For geo-physical applications, use xarray.

Cleaner fix for cartopy Stereographic projection

In previous releases, a fix to cartopy classes was done by modifying cartopy.crs module.
In this release, the fix only applies to dimarray.compat.cartopy_crs, as it should.

faster 2D interpolation

Use scipy.interpolate.RegularGridInterpolator instead of basemap interp.
This also involves new parameters for dimarray.geo.transform, dimarray.geo.transform_vectors and dimarray.interp2d , accordingly to the new underlying function.
In particular this may require the use of keyword argument bounds_error = False for new axes that are out-of-bound with respect to original axes.

0.2.3

fixed prefix in versioneer

0.2

• deprecated / removed:
  • aggregate (not useful)
  • DimArray.groupby (not really a multi-dimensional operation, alternative: dima.to_pandas().groupby(...) )
• modified behavior
  • multi-dimension indexing : now "orthogonal" by default. Use DimArray.take(..., broadcast=True) to broadcast arrays on the same axis, consistently with numpy.
• renamed:
  • DimArray.group => DimArray.flatten
  • DimArray.ungroup => DimArray.unflatten
  • GroupedAxis => MultiAxis
  • align_axes => align
• new features:
  • align : new join= parameter "inner" or "outer"
  • slicing on ordered numerical axis : a[2.:4.] on [1.5, 2.5, 3.5, 4.5] now works and return values on [2.5, 3.5]
  • open_nc to return a DatasetOnDisk : allow examination of datasets without actually reading it (somewhere between read_nc and the original netCDF4 module)
  • DimArray.iloc, DimArray.loc, DimArray.sel, DimArray.isel: convergence toward xray/pandas API
  • DimArray.nloc : like DimArray.loc but nearest-neighbor indexing
  • numpy.datetime64 can now be written to netCDF, and converted back (conversion adapted from on xray.conventions functions)
• internal:
  • indexing rewritten from the bottom up (basically: numpy.argsort + searchsorted and subsequent check, when more than one element is searched, nonzero otherwise)
    ==> much shorter source code
    ==> more efficient calculations (reindexing-speed comparable with xray, a factor 2 slower than pandas)
    ==> no dependency on pandas anymore
  • netCDF I/O rewritten, too, now relies on DatasetOnDisk, DimArrayOnDisk, AxisOnDisk, AxesOnDisk, AttrsOnDisk classes.
  • AbstractDimArray, AbstractDataset and AbstractAxis classes from which DimArray and DimArrayOnDisk derive
    ==> indexing and formatting unified
• experimental:
  • dimarray.geo.crs.get_crs() : returns an instance of a cartopy CRS class based on a dictionary of CF conventions
  • dimarray.geo.transform() : transform and interpolate a dimarray from one coordinate system to another
  • dimarray.geo.transform_array() : transform and interpolate two dimarrays

Temporary roadmap for future release(s)

Mostly, simplify and thin down the source code, make it more readable:

• dataset : do not make it an instance of OrderedDict with management of axes copy/refs as it is now, but make it a new object.
• simplify indexing in abstract classes (keep only orthogonal indexing, provide array index broadcasting as a separate function)
• simplify axes definition (allow only a few possible methods, to reduce the amount of checks)
• deprecate the dimarray.geo.GeoArray object, and flatten the sub-package for the user
  (everything accessible from dimarray.geo (not crs etc...))
• review the library of functions provided, only keep the most useful ones
• simplify the cascade of classes in the netCDF I/O part
• remove the global option file?
• improve unit tests to have less redundancy, more readability

last release before 0.2

This release is not a true release, but an intermediate milestone which contains a number of bug fixes and improvements, as well as a beta version of the geo module. It will be followed soon by a more significant update (probably 0.2 version), with improved indexing, netCDF I/O, metadata handling and Dataset functionality. These changes might introduce minor back-compatibility issues, and thus the 0.1.9 release is more useful for those who would have problems using the 0.2 version.

Summary of major changes since 0.1.8:

• bugfix:
  • added ne attribute to DimArray (a != b)
  • align (reindex) axes involving a None singleton
• dimarray.geo submodule rewritten from scratch (but still largely beta)
  • now handles transformation using cartopy
  • CF-conform transformation are automatically mapped from proj4
    arguments

improved doc and netCDF read

• new feature: read multiple netCDF4 by providing a regular expression

• minor bug fixes

• improved documentation for netCDF I/O, can now be compiled using sphinx

• also include scripts to convert notebooks to rst files and then html

  cd docs
  make rst
  make html

fewer dependency

compat folder with basemap code to use "interp"
fixed bug: no error when importing module with no netCDF4 installation

operations OK

Solved problem in operations with numpy array as LHS operator (and closed related issue)

dimarray broadcast indexing

A number of bug fixes. Dimarray was used in two big projects and a few remaining bugs were solved, mostly related to multi-dimensional indexing and array broadcasting when indexing. New attribute .box to switch from numpy-like array-broadcasting when indexing to matlab-like multi-dimensional indexing (where several dimensions are indexed independently from each other, as a "box").