4. Lua

  • 4.1. Lua tutorial

    Lua is a lightweight and compact scripting language written in the standard C language and open in source code. It is d...
    2025-10-25 13:34:11 UTC
  • 4.2. Lua environment installation

    4.2.1. Install on Linux system # It is very easy to install Lua on Linux & Mac. You only need to download thesour...
    2025-10-25 13:34:11 UTC
  • 4.3. Lua basic syntax

    Lua is very easy to learn, and we can create the first Lua program! 4.3.1. The first Lua program # Interactive pro...
    2025-10-25 13:34:08 UTC
  • 4.4. Lua data type

    Lua is a dynamically typed language, variables do not need type definition, only need to assign values to variables. The val...
    2025-10-25 13:34:08 UTC
  • 4.5. Lua variable

    Before a variable can be used, it needs to be declared in the code, that is,to create the variable. Before the compiler ex...
    2025-10-25 13:34:12 UTC
  • 4.6. Lua cycle

    In many cases, we need to do some regular repetitive operations, so we need to repeat some statements in the program. A gr...
    2025-10-25 13:34:07 UTC
  • 4.7. Lua while cycle

    In Lua programming language, the while loop statement repeatedly executes the loop body statement when the condition...
    2025-10-25 13:34:11 UTC
  • 4.8. Lua for cycle

    In Lua programming language the for loop statement can repeat the specified statement, and the number of times can b...
    2025-10-25 13:34:11 UTC
  • 4.9. Lua repeat…until cycle

    In Lua programming language repeat...until , a loop statement is different from for and while cycle for ...
    2025-10-25 13:34:09 UTC
  • 4.10. Lua loop nesting

    Lua loop is allowed to be embedded in a loop in a programming language. The following example demonstrates Lua appli...
    2025-10-25 13:34:11 UTC
  • 4.11. Lua break statement

    Lua programing language break statement is inserted into the body of the loop to exit the current loop or statement ...
    2025-10-25 13:34:10 UTC
  • 4.12. Lua goto statement

    In Lua language goto statement allows the control flow to be transferred unconditionally to the marked statement. ...
    2025-10-25 13:34:07 UTC
  • 4.13. Lua process control

    Lua programming language flow control statements are set by the program to set one or more conditional statements. When ...
    2025-10-25 13:34:08 UTC
  • 4.14. Lua if statement

    Lua if statement consists of a Boolean expression as a conditional judgment, followed by other statements. 4.14.1. ...
    2025-10-25 13:34:11 UTC
  • 4.15. Lua if…else statement

    4.15.1. If…else statement # Lua if statement can be associated with the else statement is usedtogether, in ...
    2025-10-25 13:34:10 UTC
  • 4.16. Lua if nested statement

    4.16.1. If…else statement # Lua if statement allows nesting, which means that you can use a if or else if...
    2025-10-25 13:34:10 UTC
《地理信息系统原理、技术与方法》  97

最近几年来,地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持,如城市管理、区划、环境整治等等,地理信息成为信息时代重要的组成部分之一; “数字地球”概念的提出,更进一步推动了作为其技术支撑的GIS的发展。 与此同时,一些学者致力于相关的理论研究,如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面,并且这两个方面构成了相互促进的发展过程。