我有两个熊猫数据帧df1和df2。我希望df1使用左外连接与df2结合,但使用包含“df2.Full_Key”中的“df2.Partial_key”功能的函数。左外连接熊猫数据帧使用包含
Select df1.data_id1, df1.Full_Key, df1.text_field
, df2.data_id2, df2.text_field
from df1
LEFT OUTER JOIN df2 on "df1.Full_Key contains df2.Partial_key"
有没有办法做到这一点没有for循环?鉴于
df1 = pd.DataFrame.from_items([('data_id1' , ['bzx_0001','bzx_0002','bzx_0003','bzx_0004'])
, ('Full_Key_1',['AAAA-BBBB-20150101-NS237890', 'BBBB-CCCC-21050101-MS18546', 'CCCC-CCCC-20150101-MS34567', 'CCCC-CCCC-20150101-MS34568'])
, ('text_field',['aaaaa', 'bbbbb', 'cccccc', 'ddddd'])])
df2 = pd.DataFrame.from_items([('data_id2',['dm_0001', 'dm_0002', 'dm_0003', 'dm_0004'])
,('Partial_key',['AAAA-BBBB-20150101-', 'AAAA-BBBB-20150101-', 'BBBB-CCCC-21050101-', 'XXXX-XXXX-20150101-'])
])
数据帧预期加盟后:使用循环
df_exp_res = pd.DataFrame.from_items([
('data_id1', ['bzx_0001', 'bzx_0001', 'bzx_0002', 'bzx_0003', 'bzx_0004'])
,('Full_Key_1',['AAAA-BBBB-20151005-NS237890', 'AAAA-BBBB-20151005-NS237890', 'BBBB-CCCC-21050101-MS18546', 'CCCC-CCCC-20150101-MS34567', 'CCCC-CCCC-20150101-MS34568'])
,('text_field',['aaaaa', 'aaaaa', 'bbbbb', 'cccccc', 'ddddd'])
,('data_id2', ['dm_0001', 'dm_0002', 'dm_0003', np.nan, np.nan])
,('Partial_key',['AAAA-BBBB-20151005-', 'AAAA-BBBB-20151005-', 'BBBB-CCCC-21050101-', np.nan, np.nan])
])
我的解决办法:
s = [['data_id1' , 'Full_Key_1', 'text_field', 'Partial_key', 'data_id2']]
for indx1, row1 in df1.iterrows():
fnd = False
for indx2, row2 in df2.iterrows():
if row2['Partial_key'].strip() in row1['Full_Key_1'].strip():
s.append([row1['data_id1'],row1['Full_Key_1'], \
row1['text_field'], row2['Partial_key'], \
row2['data_id2']])
fnd = True
else:
pass
else:
if not fnd:
s.append([row1['data_id1'],row1['Full_Key_1'], \
row1['text_field'], np.nan, np.nan])
pd_result_calc = pd.DataFrame(s[1:],columns=s[0])
print df1
print df2
print pd_result_calc
'Partial_key'总是截断'Full_ke y's?他们总是19个字符? – unutbu
Partial_Keys和Full_Keys没有固定长度。只要整个Partial_Key包含在被认为匹配的Full_Key中。但是,是的,Partial_Key将始终是表格的Full_Key的截断:Partial_key = Full_Key [0:some_n]其中0