根据spark数据框中的列值计算累加和和平均值

Question

我有一个spark数据框架:

Location    Month       Brand   Sector  TrueValue   PickoutValue
USA         1/1/2021    brand1  cars1   7418        30000       
USA         2/1/2021    brand1  cars1   1940        2000        
USA         3/1/2021    brand1  cars1   4692        2900        
USA         4/1/2021    brand1  cars1                           
USA         1/1/2021    brand2  cars2   16383104.2  16666667    
USA         2/1/2021    brand2  cars2   26812874.2  16666667    
USA         3/1/2021    brand2  cars2                           
USA         1/1/2021    brand3  cars3   75.6%       70.0%
USA         3/1/2021    brand3  cars3   73.1%       70.0%
USA         2/1/2021    brand3  cars3   77.1%       70.0%

我需要计算brand1, brand2的累积和brand3的累积平均值，并将这些值加载到TotalSumValue列

我期望的数据框架是:

+--------+--------+------+------+----------+------------+-------------------+-------------+
# |Location|   Month| Brand|Sector| TrueValue|PickoutValue| month_in_timestamp|TotalSumValue|
# +--------+--------+------+------+----------+------------+-------------------+-------------+
# |     USA|1/1/2021|brand1| cars1|      7418|       30000|2021-01-01 00:00:00|       7418.0|
# |     USA|2/1/2021|brand1| cars1|      1940|        2000|2021-01-02 00:00:00|       9358.0|
# |     USA|3/1/2021|brand1| cars1|      4692|        2900|2021-01-03 00:00:00|      14050.0|
# |     USA|4/1/2021|brand1| cars1|      null|        null|2021-01-04 00:00:00|      14050.0|
# |     USA|1/1/2021|brand2| cars2|16383104.2|    16666667|2021-01-01 00:00:00|   16383104.2|
# |     USA|2/1/2021|brand2| cars2|26812874.2|    16666667|2021-01-02 00:00:00|   43195978.4|
# |     USA|3/1/2021|brand2| cars2|      null|        null|2021-01-03 00:00:00|   43195978.4|
# |     USA|1/1/2021|brand3| cars3|      75.6|        70.0|2021-01-01 00:00:00|         75.6|
# |     USA|2/1/2021|brand3| cars3|      77.1|        70.0|2021-01-02 00:00:00|         76.4|
# |     USA|3/1/2021|brand3| cars3|      73.1|        70.0|2021-01-03 00:00:00|         75.3|
# +--------+--------+------+------+----------+------------+-------------------+-------------+

我尝试用这个代码，但我得到null

windowval=(Window.partitionBy('Location','Brand').orderBy('month_in_timestamp')
.rangeBetween(Window.unboundedPreceding, 0))
df = df.withColumn('TotalSumValue',
F.when(F.col('Brand').isin('brand1', 'brand2'), F.sum('TrueValue').over(windowval)),
F.when(F.col('Brand').isin('brand3'), F.avg('TrueValue').over(windowval)))

Answer 1

当您想要填充单个列时，您需要链接when()子句:

windowval=(Window.partitionBy('Location','Brand').orderBy('month_in_timestamp')
.rangeBetween(Window.unboundedPreceding, 0))
df = df.withColumn('TotalSumValue',
F.when(F.col('Brand').isin('brand1', 'brand2'), F.sum('TrueValue').over(windowval)) 
.when(F.col('Brand').isin('brand3'), F.avg('TrueValue').over(windowval)))