help labdu
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Title

     labdu -- Drop unused value labels from memory or delete values from value
labels


Syntax

        labdu [lblname-list] [, delete keep current report dryrun]


Description

    labdu drops unused value labels from memory. Optionally, values that do
    no occur in the current dataset are deleted from value labels.  If
    lblname-list is not specified it defaults to all value labels in memory.


Options

    delete deletes values and the associated text from value labels if values
        do not occur in any variable using the respective value label.

    keep does not drop value labels that are currently not used from memory.
        May only be specified with delete.

    current drops value labels not used in the current label language.

    report displays dropped value label names and values that are deleted
        from value labels.

    dryrun displays unused value labels and values that do not occur in the
        dataset. No value labels will be dropped and no values will be
        deleted. dryrun implies report.


Examples

        . sysuse nlsw88
        . label define unused 1 "something"
        . drop if race == 1
        . labdu ,delete report


Saved results

    labdu saves the following in r():

    Macros
      r(dropped)     dropped value labels (if dryrun is not specified)
      r(unused)      unused value labels (only if dryrun is specified)


Acknowledgments

    Option current is adopted from Jeroen Weesie's labelrename.


Author

    Daniel Klein, University of Bamberg, klein.daniel.81@gmail.com


Also see

    Online: label

    if installed: labdel, labeldup, labutil2