Match the Data Exported to the Precision of Wired Values in LabVIEW

Updated Nov 29, 2023

Reported In

Software

  • LabVIEW

Issue Details

  • When I export data from a LabVIEW graph or chart, the data generated does not have the same precision as the values wired to the graph or chart.  How can I control the precision of exported data? 
  • I'm acquiring voltage data that is in a mV range and I was able to debug and see that the values are correctly read by LabVIEW. However, when plotting the data to a chart, even with the Y scale in auto mode, I can only see values close to 0, as shown below:
     
When I right click on the waveform chart and go to Export Data >> Export Data to Clipboard and paste it on a spreadsheet, the amplitude values are all 0, as in the following image:
 

Solution

The format and precision of data exported from a LabVIEW graph or chart is not determined by the numeric representation of data wired to it, but rather the display format of the graph or chart's axes.  Therefore, changing the display format and precision of each axis will allow you to also change the format and precision of exported data.  Complete the following steps to change the format and precision of a graph or chart axis:
 
  1. Right-click the graph or chart and select Properties3D Plot Properties, or 3D Graph Properties.
  2. Select the Display Format or Format tab.
  3. Select the axis you want to configure.
  4. Select a format from Type. If the representation of the numbers on the scale is floating-point, you cannot display the numbers on the axis as hexadecimal, octal, or binary.
  5. Use Digits and Precision Type to change the precision of the numbers on the axis.
     
  6. Note: Select Advanced editing mode to enter format strings and customize the precision of numbers on the axes.
  7. Click OK.
After running the VI again, you will notice that the Y scale is now displaying a more precise range
 
 
and the data copied to the clipboard will also include that precision information for the amplitudes.