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Josh Rosen commented on SPARK-14932: ------------------------------------ I think that there's a similar issue impacting the Scala / Java equivalent of this API. Running {code} df.na.replace("*", Map[String, String]("NULL" -> null)) {code} will produce the exception {code} java.lang.IllegalArgumentException: Unsupported value type java.lang.String (NULL). at org.apache.spark.sql.DataFrameNaFunctions.org$apache$spark$sql$DataFrameNaFunctions$$convertToDouble(DataFrameNaFunctions.scala:436) at org.apache.spark.sql.DataFrameNaFunctions$$anonfun$4.apply(DataFrameNaFunctions.scala:348) at org.apache.spark.sql.DataFrameNaFunctions$$anonfun$4.apply(DataFrameNaFunctions.scala:348) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244) at scala.collection.immutable.Map$Map1.foreach(Map.scala:109) at scala.collection.TraversableLike$class.map(TraversableLike.scala:244) at scala.collection.AbstractTraversable.map(Traversable.scala:105) at org.apache.spark.sql.DataFrameNaFunctions.replace0(DataFrameNaFunctions.scala:348) at org.apache.spark.sql.DataFrameNaFunctions.replace(DataFrameNaFunctions.scala:313) {code} The "convertToDouble" appearing in the stracktrace is because the pattern match at https://github.com/apache/spark/blob/v2.0.2/sql/core/src/main/scala/org/apache/spark/sql/DataFrameNaFunctions.scala#L345 doesn't have a case to handle nulls so it ends up falling through to the convertToDouble case. I bet this will be easy to fix: just add a {{case null: }} at the start of the pattern match, then do a change similar to what [~nchammas] is suggesting here to fix things for Python users. > Allow DataFrame.replace() to replace values with None > ----------------------------------------------------- > > Key: SPARK-14932 > URL: https://issues.apache.org/jira/browse/SPARK-14932 > Project: Spark > Issue Type: Improvement > Components: SQL > Reporter: Nicholas Chammas > Priority: Minor > > Current doc: > http://spark.apache.org/docs/1.6.1/api/python/pyspark.sql.html#pyspark.sql.DataFrame.replace > I would like to specify {{None}} as the value to substitute in. This is > currently > [disallowed|https://github.com/apache/spark/blob/9797cc20c0b8fb34659df11af8eccb9ed293c52c/python/pyspark/sql/dataframe.py#L1144-L1145]. > My use case is for replacing bad values with {{None}} so I can then ignore > them with {{dropna()}}. > For example, I have a dataset that incorrectly includes empty strings where > there should be {{None}} values. I would like to replace the empty strings > with {{None}} and then drop all null data with {{dropna()}}. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org