We look at the demo text file, some of the recorded data is as follows, the first column is the sampling point, and the second column is the sine value: Then write the program on the block diagram:įirst pop up a dialog box and select the file:Ĭlick OK and the waveform chart records the sine of 100 points: In this section we make an example: draw a sinusoid in real time and store the drawing data in a text file.įirst create a new text file on the desktop to store the data, and name it 'demo.txt' as follows: If you need to store the data as a text file, you must first convert the data to a string to store. However, compared with other types of files, it consumes relatively large hard disk space, slower read and write speeds, and cannot write or read data at specified locations. Word、Excel Such third-party software is open, so the versatility of this type of file is more Strong. This type of file is the most common and can be found in Notepad. Text file will string ASCII The encoding format is stored in a file, such as txt Documents and Excel file. So LabVIEW provides powerful file I/O functions that allow us to create, open, and close files read and write data move or rename files and directories and change file attributes.įirst, read the written text file 1.1 Writing a text file You can add “Transpose 2D Array” for the 2D array if needed.For a complete test system or data acquisition system, we often need to store the data in a file in a format to save the data. This program does the job without converting the 2D array. A tab string is added afterwards to keep format the same. The file position is set at the end and the offset is changed to -2 to delete the carriage symbol. I set the file position (“Set File Position”) each time when a row is writen, as shown below The method I used is simple, but took me a while to come up with. But LabVIEW just automatically start a new line for each iteration. Alternatively, we can write the 2D array row by row using a for loop. I don’t like this method, which is inefficient in term of space and time. We can convert the 2D array into 1D array before writing using “Reshape Array”. But when we want to convert it to a single line it is not straight forward. We know that LabVIEW can write 2D arrays directly to the text file using “Array to Spreadsheet String.vi” or “Write to Spreadsheet File.vi”. In my projects sometime I need to write a 2D array in the same line into the text file (see the figure below).

Write to text file labview