[jira] [Created] (SPARK-12806) Support SQL expressions extracting values from VectorUDT

["Feynman Liang (JIRA)" <ji...@apache.org>]

Feynman Liang created SPARK-12806:
-------------------------------------

             Summary: Support SQL expressions extracting values from VectorUDT
                 Key: SPARK-12806
                 URL: https://issues.apache.org/jira/browse/SPARK-12806
             Project: Spark
          Issue Type: Improvement
          Components: MLlib, SQL
    Affects Versions: 1.6.0
            Reporter: Feynman Liang


Use cases exist where a specific index within a {VectorUDT} column of a {DataFrame} is required. For example, we may be interested in extracting a specific class probability from the {probabilityCol} of a {LogisticRegression} to compute losses. However, if {probability} is a column of {df} with type {VectorUDT}, the following code fails:

{code}
df.select("probability.0")

AnalysisException: u"Can't extract value from probability"
{code}

thrown from {sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/complexTypeExtractors.scala}.

{VectorUDT} essentially wraps a {StructType}, hence one would expect it to support value extraction Expressions in an analogous way.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org