help xtpatternvar 
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Generate string variable describing panel patterns


Syntax

        xtpatternvar [if] [in] , generate(newvar)


Description

    xtpatternvar generates a string variable holding information on panel
    patterns in a style similar to the output of xtdescribe.  The pattern is
    a character string, "1" for every time unit that is present in the panel
    in which each observation is included and "." for every time unit that is
    not present in that panel. Note that the symbol "." has here nothing to
    do with missing values.


Remarks

    A panel variable and a time variable must have been previously specified;
    use xtset.

    xtpatternvar will not perform if the maximum length of panel exceeds 244,
    as then the resulting pattern can not be held in a Stata string variable.

    The resulting string variable could impose substantial storage
    requirements in a large dataset.


Options

    generate() specifies the name of a new variable to be generated.  This is
        a required option.


Examples 

    . webuse abdata
    . xtset
    . xtpatternvar, gen(pattern)
    . tab pattern
    . whatever if strpos(pattern, "11111111")


Author 

    Nicholas J. Cox, Durham University
    n.j.cox@durham.ac.uk


Acknowledgments

    This program grew from a Statalist question by Abdul Berâ.  Stephen
    Jenkins provided encouragement.


Also see

    Manual:  [XT] xtdescribe