如何从 Spark Dataframe 中的 Row 对象获取值? [英] How to get a value from the Row object in Spark Dataframe?

问题描述

为了

averageCount = (wordCountsDF
                .groupBy().mean()).head()

我明白

行(平均(计数)=1.6666666666666667)

Row(avg(count)=1.6666666666666667)

但是当我尝试时:

averageCount = (wordCountsDF
                .groupBy().mean()).head().getFloat(0)

我收到以下错误:

属性错误:getFloat--------------------------------------------------------------------------- AttributeError Traceback(最近调用最后) 在 ()1 # TODO:替换为适当的代码----> 2 averageCount = (wordCountsDF3 .groupBy().mean()).head().getFloat(0)45 打印平均计数

AttributeError: getFloat --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) in () 1 # TODO: Replace with appropriate code ----> 2 averageCount = (wordCountsDF 3 .groupBy().mean()).head().getFloat(0) 4 5 print averageCount

/databricks/spark/python/pyspark/sql/types.py 在 getattr(self,item) 1270 引发 AttributeError(item) 1271
除了值错误:-> 1272 raise AttributeError(item) 1273 1274 def setattr(self, key, value):

/databricks/spark/python/pyspark/sql/types.py in getattr(self, item) 1270 raise AttributeError(item) 1271
except ValueError: -> 1272 raise AttributeError(item) 1273 1274 def setattr(self, key, value):

属性错误:getFloat

AttributeError: getFloat

我做错了什么?

推荐答案

我想通了.这将返回值:

I figured it out. This will return me the value:

averageCount = (wordCountsDF
                .groupBy().mean()).head()[0]

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