从Pandas DataFrame创建复杂的嵌套字典

不太简洁，但这是我现在能得到的最好的：

>>> def rollup1(x):...     return x.set_index('test')[['grade', 'pass']].to_dict(orient='index')>>> def rollup2(x):...     return x.groupby('course').apply(rollup1).to_dict()>>> def rollup3(x):...     return x.groupby('study').apply(rollup2).to_dict()>>> df = dat.groupby(['name','age','gender']).apply(rollup3)>>> df.name = 'study'>>> res = df.reset_index(level=[1,2]).to_dict(orient='index')>>> pprint.pprint(res){'Henry': {'age': 31L,'gender': 'Male','study': {'Physics': {'Quantum mechanics': {'Exam1': {'grade': 'C',          'pass': True},'Exam2': {'grade': 'C',          'pass': True}}}}}, 'John': {'age': 24L,          'gender': 'Male',          'study': {'Mathematics': {'Calculus 101': {'Essay': {'grade': 'A',        'pass': True},         'Exam': {'grade': 'A',       'pass': True}},   'Calculus 102': {'Exam': {'grade': 'B',       'pass': True}}},         'Philosophy': {'Aristotelean Ethics': {'Essay': {'grade': 'A',   'pass': True}}}}}}

想法是将数据汇总到字典中，同时对数据进行分组以获取“研究”列

更新
我一直在努力，创造更多的通用的解决方案，所以它会为问题的工作像这一个还有：

def rollup_to_dict_core(x, values, columns, d_columns=None):    if d_columns is None:        d_columns = []    if len(columns) == 1:        if len(values) == 1: return x.set_index(columns)[values[0]].to_dict()        else: return x.set_index(columns)[values].to_dict(orient='index')    else:        res = x.groupby([columns[0]] + d_columns).apply(lambda y: rollup_to_dict_core(y, values, columns[1:]))        if len(d_columns) == 0: return res.to_dict()        else: res.name = columns[1] res = res.reset_index(level=range(1, len(d_columns) + 1)) return res.to_dict(orient='index')def rollup_to_dict(x, values, d_columns=None):    if d_columns is None:        d_columns = []    columns = [c for c in x.columns if c not in values and c not in d_columns]    return rollup_to_dict_core(x, values, columns, d_columns)>>> pprint(rollup_to_dict(dat, ['pass', 'grade'], ['age','gender'])){'Henry': {'age': 31L,'gender': 'Male','study': {'Physics': {'Quantum mechanics': {'Exam1': {'grade': 'C',          'pass': True},'Exam2': {'grade': 'C',          'pass': True}}}}}, 'John': {'age': 24L,          'gender': 'Male',          'study': {'Mathematics': {'Calculus 101': {'Essay': {'grade': 'A',        'pass': True},         'Exam': {'grade': 'A',       'pass': True}},   'Calculus 102': {'Exam': {'grade': 'B',       'pass': True}}},         'Philosophy': {'Aristotelean Ethics': {'Essay': {'grade': 'A',   'pass': True}}}}}}