[
https://issues.apache.org/jira/browse/SPARK-23291?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16463280#comment-16463280
]
Hyukjin Kwon commented on SPARK-23291:
--------------------------------------
[~cloud_fan], you feel like we should backport this? I was looking through PRs
for backporting thing and seems we better backport it with a note in migration
guide.
I think it was just a bad design mistake. It doesn't even match to R's one.
Workaround should relatively easy if users are aware of this change.
If you feel about backporting it too, I would rather like to backport this.
> SparkR : substr : In SparkR dataframe , starting and ending position
> arguments in "substr" is giving wrong result when the position is greater
> than 1
> ------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Key: SPARK-23291
> URL: https://issues.apache.org/jira/browse/SPARK-23291
> Project: Spark
> Issue Type: Bug
> Components: SparkR
> Affects Versions: 2.1.2, 2.2.0, 2.2.1, 2.3.0
> Reporter: Narendra
> Assignee: Liang-Chi Hsieh
> Priority: Major
> Fix For: 2.4.0
>
>
> Defect Description :
> -----------------------------
> For example ,an input string "2017-12-01" is read into a SparkR dataframe
> "df" with column name "col1".
> The target is to create a a new column named "col2" with the value "12"
> which is inside the string ."12" can be extracted with "starting position" as
> "6" and "Ending position" as "7"
> (the starting position of the first character is considered as "1" )
> But,the current code that needs to be written is :
>
> df <- withColumn(df,"col2",substr(df$col1,7,8)))
> Observe that the first argument in the "substr" API , which indicates the
> 'starting position', is mentioned as "7"
> Also, observe that the second argument in the "substr" API , which indicates
> the 'ending position', is mentioned as "8"
> i.e the number that should be mentioned to indicate the position should be
> the "actual position + 1"
> Expected behavior :
> ----------------------------
> The code that needs to be written is :
>
> df <- withColumn(df,"col2",substr(df$col1,6,7)))
> Note :
> -----------
> This defect is observed with only when the starting position is greater than
> 1.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org
