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The right way to convert a column ?

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#321 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
15/100
Issue type
Documentation
Clarity
Needs clarification
Activity status
Stale
Tech stack
scala, spark
Domain
data

Research direction

No file or test is named. Start by reviewing Frameless's column transformation APIs, especially withColumnTuple and dropTuple, alongside the Spark DataFrame equivalent described in the issue. Done would be a clear, documented recommendation for converting the string column to Seq[String], including whether an additional case class is needed.

Written by the indexing model from the issue text.

Description

documentation

Hello,
I am starting with Frameless and I am having a hard time converting my code based on spark-Dataframes to the Frameless framework.
The blocking point I reach now is how to override a column.

Let's say I have a dataframe with col1,col2,..., myColumn .
myColumn is a String and it was an export from a database where this column is actually a Seq[String] so I now need to convert it back to it's type.
I used to do

df
  .withColumn("myColumn", toArray($"myColumn")

How would you do the same thing with Frameless ? Do you need two case class ? And use withColumnTuple and dropTuple ?

Dominant language
Scala
Stars
895
Forks
135
Avg merge
1d 16h
Merged PRs (30d)
3

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