![]() Use the following basic guidelines to determine which format to use: The format you use depends on the data you acquire or create and the applications that will access that data. You can read data from or write data to files in three formats-text, binary, and datalog. The File I/O VIs you use depend on the format of the files. Although these VIs are not always as efficient as the low-level functions, you might find them easier to use. However, some high-level File I/O VIs designed for common file I/O operations perform all three steps. Most File I/O VIs and functions perform only one step in a file I/O operation. After the file opens, a refnum represents the file. Indicate where an existing file resides or where you want to create a new file by specifying a path or responding to a dialog box to direct LabVIEW to the file location. Use the low-level VIs and functions to control each file I/O operation individually.Ī typical file I/O operation involves the following process.ġ. Use the high-level VIs to perform common I/O operations. To write an array of numerics to a spreadsheet using the Write to Spreadsheet File VI, you must format the array with the Array to Spreadsheet String function and specify a format and a delimiter. For example, Microsoft Excel expects strings that include delimiters, which Excel uses to segregate numbers or words into cells.įor example, to write a 1D array of numerics to a spreadsheet using theWrite File function, you must format the array into a string and separate each numeric with a delimiter, such as a tab. To use data in another VI, function, or application, you often must convert the data to a string and then format the string in a way that the VI, function, or application can read. Rotate and reverse text within a string.Find and retrieve matching patterns within a string.Change all text in a string to upper case or lower case.Search for, retrieve, and replace characters or substrings within a string.Use the String functions located on the Functions»String palette to edit strings in the following ways: You format strings for use in other applications, such as word processing applications and spreadsheets, or for use within other VIs and functions. On the front panel, strings appear as tables, text entry boxes, and labels.Edit and manipulate strings with the String functions on the block diagram. Instructing or prompting the user with dialog boxes.To store numerics in an ASCII file, you must first convert numerics to strings before writing the numerics to a disk file. Passing numeric data as character strings to instruments and then converting the strings to numerics.Learn the execution order of a property node.Ī string is a sequence of displayable or non-displayable ASCII characters.Strings provide a platform-independent format for information and data.Some of the more common applications of strings include the following: Learn to access files through a user interface. Objective Learn the various string display types. In addition, property nodes will be introduced as a means of changing front panel objects programmatically. You will also write simple VIs to write and read to and from files in LabVIEW as a form of data management. IntroductionIn this homework, you will learn about strings. ![]()
0 Comments
Leave a Reply. |