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apache spark - pyspark dataframe filter or include based on list

I am trying to filter a dataframe in pyspark using a list. I want to either filter based on the list or include only those records with a value in the list. My code below does not work:

# define a dataframe
rdd = sc.parallelize([(0,1), (0,1), (0,2), (1,2), (1,10), (1,20), (3,18), (3,18), (3,18)])
df = sqlContext.createDataFrame(rdd, ["id", "score"])

# define a list of scores
l = [10,18,20]

# filter out records by scores by list l
records = df.filter(df.score in l)
# expected: (0,1), (0,1), (0,2), (1,2)

# include only records with these scores in list l
records = df.where(df.score in l)
# expected: (1,10), (1,20), (3,18), (3,18), (3,18)

Gives the following error: ValueError: Cannot convert column into bool: please use '&' for 'and', '|' for 'or', '~' for 'not' when building DataFrame boolean expressions.

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1 Answer

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by (71.8m points)

what it says is "df.score in l" can not be evaluated because df.score gives you a column and "in" is not defined on that column type use "isin"

The code should be like this:

# define a dataframe
rdd = sc.parallelize([(0,1), (0,1), (0,2), (1,2), (1,10), (1,20), (3,18), (3,18), (3,18)])
df = sqlContext.createDataFrame(rdd, ["id", "score"])

# define a list of scores
l = [10,18,20]

# filter out records by scores by list l
records = df.filter(~df.score.isin(l))
# expected: (0,1), (0,1), (0,2), (1,2)

# include only records with these scores in list l
df.filter(df.score.isin(l))
# expected: (1,10), (1,20), (3,18), (3,18), (3,18)

Note that where() is an alias for filter(), so both are interchangeable.


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