pandas 数据框中的 StopIteration 问题与字典 python

Question

我有 3 列（DM1_ID、DM2_ID、对）pandas 数据框，有 100 万 records.Also，我有一个包含键和多个值的字典。该函数检查字典值并获取键并将该键放入 new_ID 字段中。函数在 pandas 数据帧的一小部分工作正常，但当我将它应用于整个数据帧时，它会给我“StopIteration”错误。

        DM1_ID      DM2_ID       pairs
86503   11945.0     11945.0     [11945.0, 11945.0]
86504   11945.0     362380.0    [11945.0, 362380.0]
86505   11945.0     538395.0    [11945.0, 538395.0]
86506   538395.0    591587.0    [11945.0, 591587.0]
86507   11946.0     11946.0     [11946.0, 11946.0]
86508   362380.0    200589       [362380.0,  200589.0]
86509   564785.0    11946.0     [564785.0, 11946.0]

f = lambda x: next(k for k,v in jdic.items() if any(i in v for i in x))

jdic = {10045: [1, 6, 7,10045, 15, 45, 55, 80], 11945: [11945, 362380,20589, 10, 27, 538395, 591587], 3: [3, 21, 28, 32, 35], 11946: [11946, 39, 564785]}


largeFile13000['new_ID'] = largeFile13000['pairs'].apply(f)
largeFile13000.drop('pairs', axis=1, inplace=True)
largeFile13000.head()


# final result I'm expecting is
        DM1_ID     DM2_ID        new_ID
86503   11945.0    11945.0       11945
86504   11945.0    362380.0      11945
86505   11945.0    538395.0      11945
86506   538395.0   591587.0      11945
86507   11946.0    11946.0       11946  
86508   362380.0   200589        11945
86509   564785.0   11946.0       11946




# error

StopIteration                             Traceback (most recent call last)
<ipython-input-14-ddbcd19d6baa> in <module>
----> 1 largeFile13000['new_ID'] = largeFile13000['pairs'].apply(f)
      2 largeFile13000.drop('pairs', axis=1, inplace=True)
      3 largeFile13000.head()

c:\users\ravindu\appdata\local\programs\python\python37\lib\site-packages\pandas\core\series.py in apply(self, func, convert_dtype, args, **kwds)
   3589             else:
   3590                 values = self.astype(object).values
-> 3591                 mapped = lib.map_infer(values, f, convert=convert_dtype)
   3592 
   3593         if len(mapped) and isinstance(mapped[0], Series):

pandas\_libs\lib.pyx in pandas._libs.lib.map_infer()

<ipython-input-12-b4ce01c34c30> in <lambda>(x)
----> 1 f = lambda x: next(k for k,v in jdic.items() if any(i in v for i in x))

StopIteration:

有谁能帮我解决这个问题吗？提前致谢。

Answer 1

从你的数据来看，基本上你只需要查找一列，比如“DM1_ID”，因为相应的“DM2_ID”应该属于 jdic 中的同一个键。在这种情况下，这很容易做到。我会反转你的字典。

jdic = {10045: [1, 6, 7,10045, 15, 45, 55, 80], 11945: [11945, 362380,20589, 10, 27, 538395, 591587], 3: [3, 21, 28, 32, 35], 11946: [11946, 39, 564785]}

ndic = {}
for key in jdic:
    for i in jdic[key]:
        ndic[i] = key

然后应用条件。

largeFile13000['new_ID'] = largeFile13000['DM1_ID'].apply(lambda x: ndic[x])

顺便说一句，我不知道你是否有任何特定的理由要这样构造字典jdic。对于这种明显的 many-to-one 关系，最好使用 'many' 侧作为键。

pandas 数据框中的 StopIteration 问题与字典 python

StopIteration issue in pandas dataframe with dictionary python

python

dictionary

dataframe

pandas

stopiteration