Eh, are you talking about foldLeft and foldRight in Scala? those are not from Hadoop or Spark. They are common functions in functional languages. They 'fold' a value into a new value by apply a function to the starting value and every element of a collection. Because the op may be non-commutative, doing this left to right or right to left is different, hence two functions.
On Fri, Jan 21, 2022 at 6:59 AM Theodore J Griesenbrock <t...@ibm.com> wrote: > I discovered several instances of discussion on leftFold and rightFold in > a variety of forums, but I can not find anything related to RDD in the > official documentation: > > > https://spark.apache.org/docs/latest/api/scala/org/apache/spark/rdd/RDD.html > > It appears to be non-related to Spark, and probably something > Hadoop-related. Can you please be more specific on how leftFold and > rightFold is imported and the language you are using to implement Spark? > > Thanks! > > -T.J. > > > *T.J. Griesenbrock* > Technical Release Manager > Watson Health > He/Him/His > > +1 (602) 377-7673 (Text only) > t...@ibm.com > > IBM > > > > ----- Original message ----- > From: "Sherd Fox" <sherd...@gmail.com> > To: user@spark.apache.org > Cc: > Subject: [EXTERNAL] questions on these functions > Date: Fri, Jan 21, 2022 04:26 > > Hello sparkers, > > What were the differences for leftFold, rightFold and the fold in RDD > functions? > > I am not very clear about the usage of them. > > Thanks. > > > > > --------------------------------------------------------------------- To > unsubscribe e-mail: user-unsubscr...@spark.apache.org
