def select(self, selector) -> Selector:
"""
:param selector: A mongo-like query of the underlying dataframe
:return:
>>> _docs = [
... {'bt': 0, 'tt': 5, 'tag': 'small'},
... {'bt': 10, 'tt': 15, 'tag': 'small'},
... {'bt': 20, 'tt': 25, 'tag': 'small'},
... {'bt': 30, 'tt': 35, 'tag': 'big'},
... {'bt': 40, 'tt': 45, 'tag': 'big'},
... {'bt': 50, 'tt': 55, 'tag': 'big'}]
>>> import pandas as pd
>>> selector = MgDfSelector(_df=pd.DataFrame(_docs))
>>> len(selector)
6
>>> selection = selector.select({"tag": {"$eq": 'small'}})
>>> len(selection)
3
>>> _print_docs(selection)
{'bt': 0, 'tag': 'small', 'tt': 5}
{'bt': 10, 'tag': 'small', 'tt': 15}
{'bt': 20, 'tag': 'small', 'tt': 25}
>>> selection = selector.select({'bt': {"$gte": 20}, 'tt': {"$lt": 45}})
>>> _print_docs(selection)
{'bt': 20, 'tag': 'small', 'tt': 25}
{'bt': 30, 'tag': 'big', 'tt': 35}
"""
selector_file_func = Query(selector).match
lidx = list(map(selector_file_func, self._df.to_dict(orient='rows')))
return self.__class__(self._df[lidx])
def _selector_func(self, selector):
return Query(selector).match
def select(self, selector) -> Selector:
selector_file_func = Query(selector).match
lidx = list(map(selector_file_func, self._docs.to_dict(orient='rows')))
return self.__class__(self._docs[lidx])