Github user HyukjinKwon commented on a diff in the pull request:
https://github.com/apache/spark/pull/21249#discussion_r186364537
--- Diff: docs/sparkr.md ---
@@ -664,6 +664,6 @@ You can inspect the search path in R with
[`search()`](https://stat.ethz.ch/R-ma
- For `summary`, option for statistics to compute has been added. Its
output is changed from that from `describe`.
- A warning can be raised if versions of SparkR package and the Spark JVM
do not match.
-## Upgrading to Spark 2.4.0
+## Upgrading to SparkR 2.3.1 and above
- - The `start` parameter of `substr` method was wrongly subtracted by one,
previously. In other words, the index specified by `start` parameter was
considered as 0-base. This can lead to inconsistent substring results and also
does not match with the behaviour with `substr` in R. It has been fixed so the
`start` parameter of `substr` method is now 1-base, e.g., therefore to get the
same result as `substr(df$a, 2, 5)`, it should be changed to `substr(df$a, 1,
4)`.
+ - In SparkR 2.3.0 and earlier, the `start` parameter of `substr` method
was wrongly subtracted by one, previously. In other words, the index specified
by `start` parameter was considered as 0-base. This can lead to inconsistent
substring results and also does not match with the behaviour with `substr` in
R. In version 2.3.1 and later, it has been fixed so the `start` parameter of
`substr` method is now 1-base. As an example, `substr(lit('abcdef'), 2, 4))`
would result to `abc` in SparkR 2.3.0, and the result would be `bcd` in SparkR
2.3.1.
--- End diff --
I think it's fine since it's an example ...
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
