【正文】 ble to Display Data Complete the following steps to display a collection of mean values in a table on the front panel. 1. On the front panel, select the Express Table indicator on the Text Indicators palette and place it on the front panel to the right of the waveform graph. 2. Display the block diagram. Notice that the Table terminal appears wired to the Build Table Express VI automatically. 3. If the Build Table Express VI and the Table terminal are not selected already, click an open area on the block diagram to the left of the Build Table Express VI and the Table terminal. Drag the cursor diagonally until the selection rectangle encloses the Build Table Express VI and the Table terminal, shown at left. A moving dashed outline called a marquee highlights the Build Table Express VI, the Table terminal, and the wire joining the two. 4. Drag the objects into the While Loop to the right of the Mean terminal. Notice that the While Loop automatically resizes to enclose the Build Table Express VI and the Table termial. 5. Using the Wiring tool, wire the Mean terminal of the Sample Compression Express VI to the Signals input of the Build Table Express VI. The block diagram should appear similar to Figure 34. 7 Figure 34. Block Diagram of the Reduce Samples VI 6. Display the front panel and run the VI. 7. Click the Enable switch. The table displays the mean values of every 25 samples of the sine wave. Notice if the Enable switch is off, the table does not record the mean values. 8. Stop the VI. 9. Experiment with properties of the table by using the Table Properties dialog box. For example, try changing the number of columns to one. 10. Save and close this VI. Summary The following topics are a summary of the main concepts you learned in this chapter. Using the LabVIEW Help Resources You can use the Context Help window and the LabVIEW Help to learn more about Express VIs. Both provide information that describe the functionality of the Express VI and how to configure the Express VI. The following is a summary of the different ways you learned to use the help resources in this chapter. ? The Context Help window displays basic information about LabVIEW objects when you move the cursor over each object. Objects with context help information include 8 VIs, structures, palettes, and dialog box ponents. ? When you place an Express VI on the block diagram, the Context Help window displays a brief description of the Express VI and information about how you configured the Express VI. ? You can find and select an Express VI and other block diagram objects in the LabVIEW Help. Click the Place on the block diagram button to select a block diagram object and place it on the block diagram. ? To navigate the LabVIEW Help, use the Contents, Index, and Search tabs. Use the Contents tab to get an overview of the topics and structure of the help. Use the Index tab to find a topic by keyword. Use the Search tab to search the help for a word or phrase. Customizing the Block Diagram Code There are many controls, indicators, Express VIs, and structures that you can use to customize a VI. To customize a VI, you can create controls and indicators, control when a VI stops running, and display generated data in a table. Creating Controls and Indicators Create controls and indicators that are wired to Express VIs from the block diagram by rightclicking the Express VI input, output, or wire, and selecting an option from the Create shortcut menu. Controlling When a VI Stops Running Use the While Loop to continually run the code enclosed within the loop. The While Loop stops running when a stop condition is met. When you place or move an object in a While Loop near the border, the loop automatically resizes to add space for that object. The Execution Control palette includes objects that let you control the number of times a VI runs, as well as the speed at which the VI runs. Displaying Data in a Table The table indicator displays collected data. Use the Build Table Express VI to build a table of collected data. 9 Acquiring Data and Communication with Instruments This chapter introduces you to the Express VIs you use for data acquisition and instrument munication on a PC running Windows. Refer to the LabVIEW Measurements Manual for information about data acquisition and instrument munication on all platforms. Acquiring a Signal In the following exercises, you will use the DAQ Assistant Express VI to create an NIDAQmx task. Refer to the Taking an NIDAQmx Measurement in LabVIEW help tutorial for information about additional methods you can use to create NIDAQmx tasks. To launch this help tutorial, select Help187。Numeric Indicator to create a numeric indicator. 2. Rightclick the Mean output of the Sample Compression Express VI and select Insert Input/Output from the shortcut menu to insert the Enable input. 3. Rightclick the Enable input and select Create187。VI, Function, amp。 本科畢業(yè)設(shè)計(jì)（論文） 外文翻譯原文 學(xué)生姓名： 何 曉 君 院 （系）： 電 子 工 程 學(xué) 院 專業(yè)班級 ： 測控 0602 班 指導(dǎo)教師 ： 薛 曉 書 完成日期 ： 2021 年 4 月 20 日 1 Expanding the Features of a VI You can choose one of many LabVIEW VI templates to use as a starting point. However, sometimes you need to build a VI for which a template is not available. This chapter teaches you how to build and customize a VI without using a template. Building a VI from a Blank Template In the following exercises, you will open a blank VI and add Express VIs and structures to theblock diagram to build a new VI. You will build a VI that generates a signal, reduces the number of samples in the signal, and displays the resulting data in a table on the front panel. When yo