LabVIEW程序程序框图.doc

4. Block Diagram The LabVIEW block diagram excels at conveying source code. A really good diagram is enlightening, even awe-inspiring, like a work of art. A careless diagram, however, can appear as jumbled as a bowl of spaghetti. Indeed, these two extremes are depicted by Meticulous VI and Spaghetti VI in Chapter 1, The Significance of Style. Somewhere in the middle between artwork and spaghetti is where most applications reside. Some developers have neat wiring practices but large, flat diagrams. Others have overly modular diagrams that disguise the architecture. Still others prefer variables over data flow. Many, many developers skimp on documentation to save time. Moreover, most diagrams are characterized by tradeoffs between good style and shortcuts deemed necessary to get the job done. The overall outcome is a compromise among attractive appearance, personal preferences, and functional performance. 4程序框图 LabVIEW的程序框图长于源代码表述。一个真正好的程序是发人深省的，甚至是令人敬畏的，就是一件艺术品一样。而一个差的程序，看起来就像一碗意大利面条那样凌乱。事实上，这两种极端的情况就像第一章《风格的重要性》中Meticulous VI 和 Spaghetti VI所表现的那样。而大部分程序处于艺术品和意大利面条之间。一些程序开发者有连线整齐的习惯，但程序框图往往却大而宽泛。其他的一些程序开发者却过度使用模块化编程，就像自己在搭建筑一样。而仍有一些编程人员喜欢使用变量方式而非数据流方式。很多很多开发人员在文档上节省时间。此外，很多程序是在好的风格和节约时间两者之间取得平衡下为特征下完成工作的。总体结论就是在吸引人的程序外观，个人喜好和程序功能上取得折中。 Theorem 4.1 Great LabVIEW diagrams can be expeditiously developed. Many developers wrongfully assume that attractive diagrams require a level of toil that is impractical for real-world applications that have tight deadlines. It seems faster and more productive to avoid getting caught up in diagram aesthetics. Indeed, it is possible to expend excessive time optimizing the appearance of a complex diagram, and most of us must plead guilty for doing this on occasion. However, it is always much more time consuming, in the long run, to debug and modify sloppy code. Per Theorem 1.1, applying good style significantly reduces time and effort throughout an applications life cycle. Additionally, neat development practices need not be overly time