how to replace null with 0 in scala array-CodePudding

I am a scala beginner and I face a problem when I am doing my homework because there is null in the text file for example (AFG,Asia,Afghanistan,2020-02-24,1.0,1.0,,,,,0.026,0.026). So, I need to replace the null in array with zero. I read the scala array members and try the update and filter method but I cannot solve it. Can someone help me?

    val filename = "relevant.txt" //Access File
val rf = Source.fromFile(filename).getLines.toArray //Read File as Array


for(line <- rf){ //for loop
  line.(**How to replace the null with 0?**)

  //println(line.split(",")(0))
  if (line.split(",")(0).trim().equalsIgnoreCase(iso_code)){ //check for correct ISO CODE , ignores the casing of the input
    
  total_deaths  = line.split(",")(4).trim().toDouble //increases based on the respective array position
 
  sum_of_new_deaths  = line.split(",")(5).trim().toDouble
 
  record_count  = 1 //increment for each entry

  }
}

CodePudding user response：

What you may do is something like this:

for (line <- rf) {
  val data = line.split(',').toList.map(str => Option(str).filter(_.nonEmpty))
}

That way data would be a List[Option[String]] where empty values will be None, then you may use pattern matching to extra the data you want.

CodePudding user response：

if you had to apply the change where you want:

//line.(**How to replace the null with 0?**)

you could do:

val line2 = if (line.trim().isEmpty) "," else line

then use line2 everywhere else.

As a side thing, if you want to do something more scala, replace .toArray with .toList and have a look at how map, filter, sum etc work.