8.21. Scala specifies the function parameter name

发布时间 :2023-11-15 23:00:02 UTC      

In general, the function call parameters are passed one by one according to the order of the parameters when the function is defined. However, we can also specify the parameter name of the function, and we do not need to pass the parameters to the function sequentially, as an example:

object Test {
   def main(args: Array[String]) {
        printInt(b=5, a=7);
   }
   def printInt( a:Int, b:Int ) = {
      println("Value of a : " + a );
      println("Value of b : " + b );
   }
}

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

$ scalac Test.scala
$ scala Test
Value of a :  7
Value of b :  5

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.