9. Swift

  • 9.1. Swift tutorial

    Swift, an open source programming language that supports multiple programming paradigms and compilation, was released by ...
    2025-10-25 13:33:47 UTC
  • 9.2. Swift environment building

    Swift is an open source programming language for developing OS X and iOS applications. Before the formal development of ap...
    2025-10-25 13:33:51 UTC
  • 9.3. Swift basic syntax

    In the previous chapter, we talked about how to create “Hello, World!” in the Swift language. program. Now let’s review. I...
    2025-10-25 13:33:47 UTC
  • 9.4. Swift data type

    When we program in any programming language, we need to use a variety of data types to store different information. The da...
    2025-10-25 13:33:50 UTC
  • 9.5. Swift variable

    A variable is an easy-to-use placeholder that refers to the computer’s memory address. Each variable in Swift specifies a ...
    2025-10-25 13:33:49 UTC
  • 9.6. Swift optional type

    The optional (Optional) type of Swift, which is used to handle cases where values are missing. Optional means “there is a va...
    2025-10-25 13:33:50 UTC
  • 9.7. Swift constant

    Once a constant is set, its value cannot be changed while the program is running. Constants can be any data type such as i...
    2025-10-25 13:33:47 UTC
  • 9.9. Swift operator

    An operator is a symbol that tells the compiler to perform a mathematical orlogical operation. Swift provides the followin...
    2025-10-25 13:33:51 UTC
  • 9.10. Swift conditional statement

    A conditional statement executes the program through one or more conditions set, executing the specified statement when the ...
    2025-10-25 13:33:45 UTC
  • 9.11. Swift if statement

    One if a statement consists of a Boolean expression followed by one or more statements. 9.11.1. Grammar # In Sw...
    2025-10-25 13:33:45 UTC
  • 9.12. Swift if…else statement

    One if statement can be followed by an optional else statement else statement in a Boolean expression false ...
    2025-10-25 13:33:48 UTC
  • 9.13. Swift if…else if…else statement

    One if statement can be followed by an optional else if...else statement else if...else statement is use...
    2025-10-25 13:33:46 UTC
  • 9.14. Swift nested if statement

    In the Swift language, you can use a if or else if use another within the statement if or else if statem...
    2025-10-25 13:33:50 UTC
  • 9.15. Swift switch statement

    The switch statement allows you to test when a variable is equal to multiplevalues. In the Swift language, as long as the ma...
    2025-10-25 13:33:47 UTC
  • 9.16. Swift cycle

    Sometimes, we may need to execute the same piece of code multiple times. In general, statements are executed sequentially: t...
    2025-10-25 13:33:49 UTC
  • 9.17. Swift for-in cycle

    Swift for-in loops are used to traverse all the elements in a collection, such as intervals represented by numbers, elem...
    2025-10-25 13:33:51 UTC

Principles, Technologies, and Methods of Geographic Information Systems

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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.