I think I got it. The solution was odd because it makes me wonder how does the original solution even worked. Basically I just rewrote the counter() in the parent class to return a array.distinct.length , i.e. the distinct integers or the roots: /* * takes the initial number of components * as its argument … Read more
The error is pretty self explanatory, so it is probably something simple that you are missing. Can you modify your script and run it as shown below. Please modify the “fileName” value to where you think the file is. import java.nio.file.{Paths, Files} import sys.process._ /************ Modify this line with your data’s file name **************/ val … Read more
I think this might solve your problem t.countByValue().filter(tupleOfCount=>Try(tupleOfCount._1.toInt).toOption.isEmpty).print() Use of isInstanceOf should be the last resort as @sergey said , so this code must solve the issue or else the pattern matching would be a good option too. solved Scala Filter Only Digits
type Set = Int => Boolean defines Set to mean a function from Int to Boolean. There is no ++ method on functions. That’s it. 0 solved Cannot resolve symbol ++ in Scala
You can get this done in java using any reader. e.g- BufferedReader, FileReader anything like this. public class InJava { BufferedReader br= new BufferedReader(new InputStreamReader(System.in)); // //in main() public static void main(String [] args) { Object obj= br.readLine(); } } If you are using a list use Iterator. public class InJava { List<double> lst= new … Read more
! returns the exit code of the process (0 in your case). If you need the output of the process you should use !! instead: val url = “https://morningconsult.com/alert/house-passes-employee-stock-options-bill-aimed-startups/” import sys.process._ val result = (“wget -qO- ” + url !!).toString println(“result : ” + result) (relevant documentation) solved Return value of process to String
you cannot use dataframes in RDD code (you use dataframes in days.foreach), th dataframes are null here as it only lives on the driver, but not on the executors 1 solved NullPointerException on DataFrame where
I don’t understand the question. I think you have either made a separate mistake and misattributed your error to the phantom symptom you describe in the question, or I have misunderstood you. Here is a version of your posted code, with minor tweaks that appear to me to be unrelated to your question, that compiles … Read more
May be something like this will do Steps:- 1.Split the string by space delimiter. 2.Map through the Seq of strings created in the first step and split by . delimiter. val s = “abc.def ghi.jkl mno.pqr” val strS = s.split(” “).toSeq val firstStrS = strS.map { s=> val t = s.split(‘.’).toSeq t.head }.mkString(” “) Hope … Read more
There are many ways to write test for it. There are libraries like FlatSpec, FunSuit. So here, i am going to write test case for it using FunSuit import org.scalatest.FunSuite class WordTest extends FunSuite { test(“should return word count “) { val wordCount = Word.readFile() assert(wordCount.nonEmpty) } } solved How to write scalatest unit test … Read more
The most iconic way ot do it is to unwrap values with scala is to use pattern matching to unwrap the value. entities match { case Some(queryEntities: QueryEntities) => queryEntities.entities.foreach { case e => println(e.columnFamily) println(e.fromDate.getOrElse(“defaultFromDateHere”) println(e.toDate.getOrElse(“defaultToDateHere”)) } case None => println(“No value”) } 9 solved How can I access a method which return Option … Read more
You can use List#grouped to create a non-overlapping window: list.grouped(2).map(l => (l(0), l(1))).toMap 7 solved How to convert a list of string to map in Scala?
I think the main problem is the conversion of numeric types. So let´s encode that: trait NumericConversion[X, Y] { def convert(x: X): Y } Of course one have to specify that abstract concept: (for example) implicit object Int2IntNumericConversion extends NumericConversion[Int, Int] { def convert(i: Int): Int = i } implicit object Double2DoubleNumericConversion extends NumericConversion[Double, Double] … Read more
Because x :: xs returns a new list, where the first element is x, followed by xs. So, to make your code work, make list a var and re-assign it inside the loop: var list = List[Int]() while(list.length < 20) list = Random.nextInt(100) :: list However, the idiomatic way of doing this in Scala is … Read more
You can compile Scala into a .class file (e.g. “scalac ./foo.scala”) and run methods from your Java grading program. This might be useful reference: How do you call Scala objects from Java? solved Write Java Program to grade Scala Homeworks