首页 > 解决方案 > pandas 字符串基于另一列出现在一列中的次数

问题描述

我有一个非常大的汽车数据框。像这样:

                                Text                               Terms
0       Car's model porche year in data                [tech, window, tech]
1  we’re simply making fossil fuel cars       [brakes, window, Italy, nice]
2          Year of cars Ferrari to make    [Detroit, window, seats, engine]
3     reading the specs of Ferrari file  [tech, window, engine, v8, window]
4     likelihood Porche in the car list                 [from, wheel, tech]

还有这些:

term_list = ['tech', 'engine', 'window']
cap_list = ['Ferrari', 'porche']
term_cap_dict = {'Ferrari': ['engine', 'window'], 'Porche': ['tech']}

我想要一个结果数据框来计算每个术语(在 term_list 中)出现在“术语”列中的次数 - 仅当“文本”列包含相应的“键”(来自 term_cap_dict)时才计算。例如:“tech”一词的条件计数(给定 Porche)= 3(因为相应的“Text”中包含“Porche”。......尽管“tech”出现的总次数是 4 )。如果计数为 0 或条件文本不存在,则条件计数默认为 0。所需的输出:

    Terms        Cap  ConditionalCount  
0  engine    Ferrari  2
1  engine     porche  0
2    tech    Ferrari  0
3    tech     porche  3
4  window    Ferrari  3
5  window     porche  1

这是我到目前为止所拥有的(只是计算 TotalCount...不是条件计数):

term_cap_dict = {k.lower(): list(map(str.lower, v)) for k, v in term_cap_dict.items()}
terms_counter = Counter(chain.from_iterable(df['Terms']))
terms_series = pd.Series(terms_counter)
terms_df = pd.DataFrame({'Term': terms_series.index, 'TotalCount': terms_series.values})
df1 = terms_df[terms_df['Term'].isin(term_list)]
product_terms = product(term_list, cap_list)
df_cp = pd.DataFrame(product_terms, columns=['Terms', 'Capability'])
dff = df_cp.set_index('Terms').combine_first(df1.set_index('Term')).reset_index()
dff.rename(columns={'index': 'Terms'}, inplace=True)

这给出了 TotalCount:

    Terms Capability  TotalCount
0  engine    Ferrari  3.0
1  engine     porche  3.0
2    tech    Ferrari  4.0
3    tech     porche  4.0
4  window    Ferrari  4.0
5  window     porche  4.0

从现在开始,我不知道如何计算 ConditionalCount。任何建议表示赞赏。

df.to_dict()

{'Title': {0: "Car's model porche year in data",
      1: 'we’re simply making fossil fuel cars',
      2: 'Year of cars Ferrari to make',
      3: 'reading the specs of Ferrari file',
      4: 'likelihood Porche in the car list'},
     'Terms': {0: ['tech', 'window', 'tech'],
      1: ['brakes', 'engine', 'Italy', 'nice'],
      2: ['Detroit', 'window', 'seats', 'engine'],
      3: ['tech', 'window', 'engine', 'v8', 'window'],
      4: ['from', 'wheel', 'tech']}}

标签: pythonpandas

解决方案


更新:

df1 = df.explode(column='Terms')

regcap = '|'.join(cap_list)
df1['Cap'] = df1['Text'].str.extract(f'({regcap})')
filter_df =pd.concat([pd.DataFrame({'Cap':v, 'Terms':k}) for v, k in term_cap_dict.items()])
filter_df = filter_df.apply(lambda x: x.str.lower())

df1 = df1.apply(lambda x: x.str.lower())
df1_filt = df1.merge(filter_df)
idx = pd.MultiIndex.from_product([term_list, list(map(str.lower, cap_list))], names=['Term','Cap'])
df_out = df1_filt[df1_filt['Terms'].isin(term_list)].groupby(['Terms','Cap']).count()\
                                       .rename(columns= {'Text':'Count'})\
                                       .reindex(idx, fill_value=0).reset_index()
print(df_out)

输出:

     Term      Cap  Count
0    tech  ferrari      0
1    tech   porche      2
2  engine  ferrari      2
3  engine   porche      0
4  window  ferrari      3
5  window   porche      0

IIUC,试试这个:

df1 = df.explode(column='Terms')

regcap = '|'.join(cap_list)
df1['Cap'] = df1['Text'].str.extract(f'({regcap})')

idx = pd.MultiIndex.from_product([term_list, cap_list], names=['Term','Cap'])
df_out = df1[df1['Terms'].isin(term_list)].groupby(['Terms','Cap']).count()\
                                          .rename(columns= {'Text':'Count'})\
                                          .reindex(idx, fill_value=0).reset_index()
print(df_out)

输出:

     Term      Cap  Count
0    tech  Ferrari      1
1    tech   porche      2
2  engine  Ferrari      2
3  engine   porche      0
4  window  Ferrari      3
5  window   porche      1

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