三、2019年11月自行车产品销售表现
3.1、数据源 dw_customer_order
#查看数据源
gather_customer_order.head(3)
3.2、细分市场销量表现
作业 3.2.1、gather_customer_order表利用groupby聚合月份，求每个月自行车的销售数量，赋值给变量gather_customer_order_group_month
#求每个月自行车累计销售数量
gather_customer_order_group_month = gather_customer_order.groupby('create_year_month').agg({'order_num':'sum'},axis=0).reset_index()
gather_customer_order_group_month.head()
作业 3.2.2、利用pd.merge模块合并自行车销售信息表（gather_customer_order）+自行车每月累计销售数量表(gather_customer_order_group_month)赋值变量给order_num_proportion
order_num_proportion = pd.merge(gather_customer_order,gather_customer_order_group_month,on='create_year_month',how='left')
作业 3.2.3、计算自行车销量/自行车每月销量占比,计算结果形成新的列'order_proportion'
order_num_proportion['order_proportion']=order_num_proportion['order_num_x']/order_num_proportion['order_num_y']
作业 3.2.4、重命名自行车每月销售量order_num_y为sum_month_order
#重命名sum_month_order：自行车每月销售量
order_num_proportion = order_num_proportion.rename(columns={'order_num_y':'sum_month_order'})
