8.17. Scala function-variable argument

发布时间 :2023-11-14 23:00:02 UTC      

Scala allows you to specify that the last argument to the function can be duplicated, that is, we do not need to specify the number of arguments to the function, we can pass a variable length argument list to the function.

Scala sets variable parameters (repeatable parameters) by placing an asterisk after the type of the parameter. For example:

object Test {
   def main(args: Array[String]) {
        printStrings("Runoob", "Scala", "Python");
   }
   def printStrings( args:String* ) = {
      var i : Int = 0;
      for( arg <- args ){
         println("Arg value[" + i + "] = " + arg );
         i = i + 1;
      }
   }
}

Execute the above code, and the output is as follows:

$ scalac Test.scala
$ scala Test
Arg value[0] = Runoob
Arg value[1] = Scala
Arg value[2] = Python

Principles, Technologies, and Methods of Geographic Information Systems  102

In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress.