python通识相关

通配符匹配某段 并定点替换

pattern = r's-[^>]*.ii'
replacement = r's-' + mu_str_lower + '.ii'
new_cell_value = re.sub(pattern, replacement, url_str)

dataframe某列抽取最后一个字符

df['a'] = df['a'].astype(str)
df['a_simple'] = df['a'].apply(lambda x: x[:-1])

dataframe某列求分位数

df['A'].quantile(0.25)

dataframe query

df.query('A > 2 & B < 8')
df.query('age > 40 & gender == "M"')
df.query('age > @settingage')

pandas read

df = pd.read_sql_query(sql, oracle_conn)

python大小写转换

('AF').lower()

dataframe列名大小写转换

cols = df.columns
cols_lower = [x.lower() for x in cols]
df.columns = cols_lower

requirements.txt自动生成

pip install pipreqs
ipreqs ./ --encoding=utf-8

dataframe列处理 判断 函数 字典

# map支持字典 函数
gender_dict = {'女':0, '男':1}
df['性别'] = df['性别'].map(gender_dict)
# apply支持函数