Initialization

MulDataFrame

The basic constructor signature is:

class muldataframe.MulDataFrame(data, index=None, columns=None,
    index_init=None, columns_init=None, ...)

The input to the index and columns arguments must be pandas DataFrames. The input to the data argument should follow the same rules as required by the data argument in the pandas.DataFrame constructor. The values dataframe is constructed from the data argument.

If the index or columns argument is None, an empty index or columns dataframe is created with its index being the same as the index or columns of the values dataframe. If they are not None, the final values dataframe is constructed in either of two modes as specified by the index_init and the columns_init arguments.

Overide mode

If index_init="override", the index of the index dataframe overrides the index of the values dataframe. This mode requires both indices’ lengths to be the same. Similarly, if columns_init="override", the index of the columns dataframe overrides the columns of the values dataframe. The two indices’ lengths should also be the same.

>>> import pandas as pd
>>> import muldataframe as md
>>> index = pd.DataFrame([[1,2],[3,6],[5,6]],
                     index=['a','b','b'],
                     columns=['x','y'])
>>> columns = pd.DataFrame([[5,7],[3,6]],
                    index=['c','d'],
                    columns=['f','g'])
>>> df = pd.DataFrame([[1,2],[8,9],[8,7]],index=['k','l','m'],columns=['t',5])
>>> mf = md.MulDataFrame(df, index=index,
    columns=columns, index_init='override',
    columns_init='override')
>>> mf
(3, 2)    g  7  6
          f  5  3
             c  d
--------  ---------
   x  y      c  d
a  1  2   a  1  2
b  3  6   b  8  9
b  5  6   b  8  7

Align mode

If index_init="align", the index of the index dataframe is used to index the values dataframe constructed from the data argument. The resulting indexed values dataframe is used as the final values dataframe. It requires the index of the values dataframe to be uinque and contain all the labels of the index dataframe’s index. If columns_init="align", the values dataframe is simiarly indexed on the columns dimension by the index of the columns dataframe.

>>> df = pd.DataFrame([[1,2],[8,9]],index=['a','b'],columns=['d','c'])
>>> mf2 = md.MulDataFrame(df, index=index,
    columns=columns, index_init='align',
    columns_init='align')
>>> mf2
(3, 2)    g  7  6
          f  5  3
             c  d
--------  ---------
   x  y      c  d
a  1  2   a  2  1
b  3  6   b  9  8
b  5  6   b  9  8

Default behavior

If index_init or columns_init is None, the default behavior depends on the type of the data argument. Basically, if the data argument implies an index on a dimension, the align mode will be used for that diemnsion. Otherwise, the override mode is used.

Concretely, with index_init=None, the initialization mode on the row dimension will be 'align' if data is a pandas.DataFrame or a pandas.Series object. With columns_init=None, the initialization mode on the columns dimension will be 'align' if data is a pandas.DataFrame, a dict of list-like objects or a list of dict objects.

MulSeries

The basic constructor signature is:

class muldataframe.MulSeries(data, index=None, name=None, index_init=None, ...)

The index_init argument behaves the same as that in the MulDataFrame constructor.

Name initialization

The name argument can be a string or a pandas.Series object. If name is a string, construct an empty name series using the name argument as its name. If name is None, construct an empty name series using the name of the values series as its name.