Can I Use Cursors in a LabVIEW Waveform Chart?

Updated Jan 12, 2023

Reported In

Software

  • LabVIEW

Issue Details

In my program, I would like to see the values of individual data points plotted on a chart after they are plotted, but I am having trouble doing so. I would like to use cursors as I do with Waveform Graphs. What are my options? Can I use a Waveform Graph to exhibit the same behavior as the Waveform Chart?

Solution

No, cursors are unavailable in Waveform Charts. A Waveform Chart will accept one scalar value from the block diagram while a Waveform Graph will accept an array of numeric or waveform data. For more information about charts vs. graphs, please read What Is the Difference between Graphs and Charts in LabVIEW?  

Additional Information

If your application requires chart-like data presentation, here are two options to consider:
  1. It is possible to see the exact Y value in a chart without using cursors. To see a specific value, use the Graph Palette to zoom in. If the Graph Palette is not visible, right-click the Waveform Chart and select Visible Items»Graph Palette. Then, click the zoom tool and select the window zoom tool (top-left icon). Begin tracing a window around the data point of interest until the axes indicate an exact value. To zoom back out, click the zoom tool and select the full-sized window (bottom-left icon). 
     
  2. It is possible to use a Waveform Graph in such a way that it resembles a Waveform Chart. Please see How can I have a Waveform Chart using a Waveform Graph?  in which the random number generator represents a single acquired data point. That single data point is appended at the end of the array and the first data point is deleted, keeping the array the same size and resulting in strip-like behavior on the Waveform Graph. In this workaround, however, old data is deleted unless saved in another location, making data management and zooming out difficult.