如何计算pyspark数据框中一列中每个分类变量的频率？

Question

Say I have a pyspark dataframe:

df.show()
+-----+---+
|  x  |  y|
+-----+---+
|alpha|  1|
|beta |  2|
|gamma|  1|
|alpha|  2|
+-----+---+

I want to count how many occurrence alpha , beta and gamma there are in column x . How do I do this in pyspark?

Answer 1

使用pyspark.sql.DataFrame.cube() ：

df.cube("x").count().show()