Enable LabVIEW front panel data logging for a VI using interactive options or LabVIEW properties. Logging creates a binary datalog file that records the values of controls and indicators on the front panel.

You can interactively log front panel on demand or each time a VI runs. You can programmatically log front panel data each time a VI runs.

You can use any file extension for datalog files, for example .dat or .txt. Datalog files remain binary files even if you name them with a file extention like .txt.

Note You cannot overwrite a record after LabVIEW writes it to a datalog file.

To enable front panel data logging, complete the following steps.

  1. Enable front panel data logging for the VI.
    OptionDescription
    Interactive: on demand logging
    1. Run the VI whose data you want to log.
    2. After the VI stops running, select Operate » Data Logging » Log....
    Interactive: automatic logging
    1. Select Operate » Log at Completion.
    2. Run the VI.
    Programmatic: automatic logging
    1. Enable logging for the VI with the Log at Finish property.
    2. To define the log file for the VI programmatically, specify the path to the datalog file, including the file name and extension, with the Log File Path property.
    3. Run the VI.
  2. If this is the first time you are logging the front panel data for this VI, and you did not name the datalog file earlier, LabVIEW prompts you to name the datalog file.

LabVIEW logs data each time you run the VI. LabVIEW appends a new record to the datalog file each additional time you run the VI.

Note A waveform chart logs only one data point at a time with front panel data logging. If you wire an array to the chart indicator, the datalog file contains a subset of the array the chart displays.