在 PySpark 中 - 如果列表中的值位于不同的 DataFrame 的行中，如何在 PySpark 中创建新的 DataFrame？

Question

I have a sample DataFrame in the "pyspark.sql.dataframe.DataFrame" format:

| ID | SampleColumn1| SampleColumn2 | SampleColumn3|
|--- |--------------| ------------  | ------------ |
| 1  |sample Apple  | sample Cherry | sample Lime  |
| 2  |sample Cherry | sample lemon  | sample Grape |

I would like to create a new DataFrame based off of this initial dataframe. Should one of several values in a list [Apple, Lime, Cherry] be in ANY of the columns for a row, it would appear as a 1 in the new dataframe for its column. In this case, the output should be:

listOfValues = ['Apple','Lime','Cherry']

| ID | Apple | Lime | Cherry |
| 1  |  1    |  1   |    1   |
| 2  |  0    |  0   |    1   |

I currently have the following using normal Pandas:

keywords = ['Apple', 'Lime', 'Cherry']
tmp = (df.melt(ignore_index=False)
        .value.str.extract(
            f'({"|".join(keywords)})',
            expand=False)
        .dropna())

res = (pd.crosstab(index=tmp.index, columns=tmp)
        .rename_axis(index=None, columns=None))

I would like to achieve this output but however I would like to use PySpark as the current platform does not allow use of Pandas or normal Python commands.

Answer 1

Concat all columns, iterate over each keyword and check if it exists in the new concat column. This gives you True & False . If you are interested in 1 & 0 , then use when() & otherwise().

df = spark.createDataFrame(data=[["1","sample Apple","sample Cherry","sample Lime"],["2","sample Cherry","sample lemon","sample Grape"],["3","sample nothing","sample nothing","sample nothing"]], schema=["ID","SampleColumn1","SampleColumn2","SampleColumn3"])
keywords = ['Apple', 'Lime', 'Cherry']
columns = [c for c in df.columns if c != "ID"]

df = df.select("ID", F.concat_ws(" ", *columns).alias("all"))

for k in keywords:
  df = df.withColumn(k, F.when(F.lower(F.col("all")).contains(k.lower()), F.lit(1)).otherwise(F.lit(0)))

df = df.drop("all")

[Out]:
+---+-----+----+------+
| ID|Apple|Lime|Cherry|
+---+-----+----+------+
|  1|    1|   1|     1|
|  2|    0|   0|     1|
|  3|    0|   0|     0|
+---+-----+----+------+