python - 按列值是否等于Spark中的列表进行过滤

我正在尝试根据列中的值是否等于列表来过滤Spark数据帧。我想做这样的事情:

filtered_df = df.where(df.a == ['list','of' , 'stuff'])

其中filtered_df仅包含filtered_df.a的值为['list','of' , 'stuff']且a的类型为array (nullable = true)的行。

最佳答案

更新:

在当前版本中，您可以使用文字的array:

from pyspark.sql.functions import array, lit

df.where(df.a == array(*[lit(x) for x in ['list','of' , 'stuff']]))

原始答案:

嗯，这样做有点笨拙，不需要Python批处理作业，它是这样的:

from pyspark.sql.functions import col, lit, size
from functools import reduce
from operator import and_

def array_equal(c, an_array):
    same_size = size(c) == len(an_array)  # Check if the same size
    # Check if all items equal
    same_items = reduce(
        and_,
        (c.getItem(i) == an_array[i] for i in range(len(an_array)))
    )
    return and_(same_size, same_items)

快速测试:

df = sc.parallelize([
    (1, ['list','of' , 'stuff']),
    (2, ['foo', 'bar']),
    (3, ['foobar']),
    (4, ['list','of' , 'stuff', 'and', 'foo']),
    (5, ['a', 'list','of' , 'stuff']),
]).toDF(['id', 'a'])

df.where(array_equal(col('a'), ['list','of' , 'stuff'])).show()
## +---+-----------------+
## | id|                a|
## +---+-----------------+
## |  1|[list, of, stuff]|
## +---+-----------------+

关于python - 按列值是否等于Spark中的列表进行过滤，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/36207112/