9. Swift

  • 9.18. Swift for cycle

    This loop has been deprecated in Swift 3. Swift for a loop is used to repeat a series of statements until a specific c...
    2025-10-25 13:33:48 UTC
  • 9.19. Swift While cycle

    Swift while the loop begins by calculating a single condition. If the condition is true will run a series of stateme...
    2025-10-25 13:33:47 UTC
  • 9.20. Swift repeat…while cycle

    Swift repeat...while the cycle is not like for and while the loop judges the conditional statement before the lo...
    2025-10-25 13:33:45 UTC
  • 9.21. Swift Continue statement

    Swift continue statement tells a loop body to stop this loop iteration immediately and restart the next loop iteration. ...
    2025-10-25 13:33:50 UTC
  • 9.22. Swift Break statement

    Swift break statement immediately ends the execution of the entire control flow. If you are using a nested loop (that ...
    2025-10-25 13:33:52 UTC
  • 9.23. Swift Fallthrough statement

    Swift fallthrough statement let case subsequent statements continue to run sequentially, regardless of whether the c...
    2025-10-25 13:33:47 UTC
  • 9.24. Swift string

    A Swift string is a collection of characters. For example, “Hello, World!”a collection of values of such an ordered characte...
    2025-10-25 13:33:51 UTC
  • 9.25. Swift character

    The character of Swift is a single character string literal, and the data type is Character . The following example li...
    2025-10-25 13:33:48 UTC
  • 9.26. Swift array

    Swift arrays use ordered lists to store multiple values of the same type. The same value can appear multiple times in differ...
    2025-10-25 13:33:44 UTC
  • 9.27. Swift dictionary

    Swift dictionaries are used to store unordered collections of data of the same type. Swift dictionaries force the type of el...
    2025-10-25 13:33:45 UTC
  • 9.28. Swift function

    A separate block of code that the Swift function uses to accomplish a specific task. Swift uses a unified syntax to repres...
    2025-10-25 13:33:46 UTC
  • 9.29. Swift closure

    Closures are self-contained blocks of functional code that can beused in code or used as parameters to pass values. Closur...
    2025-10-25 13:33:48 UTC
  • 9.30. Swift enumeration

    Enumeration is simply a data type, except that this data type contains only custom-specific data, which is a collection of d...
    2025-10-25 13:33:48 UTC
  • 9.31. Swift structure

    The Swift structure is a general and flexible construct used to build code. We can extend the function of the structure by...
    2025-10-25 13:33:48 UTC
  • 9.32. Swift class

    The Swift class is a generic and flexible construct used to build code. We can define properties (constants, variables) an...
    2025-10-25 13:33:44 UTC
  • 9.33. Swift attribute

    The Swift property associates a value with a specific class, structure, or enumeration. Attributes can be divided into sto...
    2025-10-25 13:33:46 UTC

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.