Interactive online version:

Compatibility with pandas

Import the LArray library:

from larray import *

To convert an Array object into a pandas DataFrame, the method to_frame can be used:

pop = load_example_data('demography_eurostat').pop
pop

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-2-cfdf11435826> in <module>
----> 1 pop = load_example_data('demography_eurostat').pop
      2 pop

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/example.py in load_example_data(name)
     91     if name not in AVAILABLE_EXAMPLE_DATA.keys():
     92         raise ValueError("example_data must be chosen from list {}".format(list(AVAILABLE_EXAMPLE_DATA.keys())))
---> 93     return la.Session(AVAILABLE_EXAMPLE_DATA[name])

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/core/session.py in __init__(self, *args, **kwargs)
     94             if isinstance(a0, str):
     95                 # assume a0 is a filename
---> 96                 self.load(a0)
     97             else:
     98                 # iterable of tuple or dict-like

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/core/session.py in load(self, fname, names, engine, display, **kwargs)
    426         else:
    427             handler = handler_cls(fname)
--> 428         metadata, objects = handler.read(names, display=display, **kwargs)
    429         for k, v in objects.items():
    430             self[k] = v

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/inout/common.py in read(self, keys, *args, **kwargs)
    128                 print("loading", type, "object", key, "...", end=' ')
    129             try:
--> 130                 res[key] = self._read_item(key, type, *args, **kwargs)
    131             except Exception:
    132                 if not ignore_exceptions:

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/inout/hdf.py in _read_item(self, key, type, *args, **kwargs)
    137         else:
    138             raise TypeError()
--> 139         return read_hdf(self.handle, hdf_key, *args, **kwargs)
    140
    141     def _dump_item(self, key, value, *args, **kwargs):

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/inout/hdf.py in read_hdf(filepath_or_buffer, key, fill_value, na, sort_rows, sort_columns, name, **kwargs)
     81             cartesian_prod = writer != 'LArray'
     82             res = df_asarray(pd_obj, sort_rows=sort_rows, sort_columns=sort_columns, fill_value=fill_value,
---> 83                              parse_header=False, cartesian_prod=cartesian_prod)
     84             if _meta is not None:
     85                 res.meta = _meta

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/inout/pandas.py in df_asarray(df, sort_rows, sort_columns, raw, parse_header, wide, cartesian_prod, **kwargs)
    338         unfold_last_axis_name = isinstance(axes_names[-1], basestring) and '\\' in axes_names[-1]
    339         res = from_frame(df, sort_rows=sort_rows, sort_columns=sort_columns, parse_header=parse_header,
--> 340                          unfold_last_axis_name=unfold_last_axis_name, cartesian_prod=cartesian_prod, **kwargs)
    341
    342     # ugly hack to avoid anonymous axes converted as axes with name 'Unnamed: x' by pandas

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/inout/pandas.py in from_frame(df, sort_rows, sort_columns, parse_header, unfold_last_axis_name, fill_value, meta, cartesian_prod, **kwargs)
    241             raise ValueError('sort_rows and sort_columns cannot not be used when cartesian_prod is set to False. '
    242                              'Please call the method sort_axes on the returned array to sort rows or columns')
--> 243         axes_labels = index_to_labels(df.index, sort=False)
    244
    245     # Pandas treats column labels as column names (strings) so we need to convert them to values

~/checkouts/readthedocs.org/user_builds/larray/conda/0.32/lib/python3.6/site-packages/larray-0.32-py3.6.egg/larray/inout/pandas.py in index_to_labels(idx, sort)
     41     Returns unique labels for each dimension.
     42     """
---> 43     if isinstance(idx, pd.core.index.MultiIndex):
     44         if sort:
     45             return list(idx.levels)

AttributeError: module 'pandas.core' has no attribute 'index'

df = pop.to_frame()
df

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-3-002a3ec9888d> in <module>
----> 1 df = pop.to_frame()
      2 df

NameError: name 'pop' is not defined

Inversely, to convert a DataFrame into an Array object, use the function asarray:

pop = asarray(df)
pop

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-4-5f4fb93339cc> in <module>
----> 1 pop = asarray(df)
      2 pop

NameError: name 'df' is not defined