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help for pieplot
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Plot pie charts of categorical frequencies 

        pieplot yvar [xvar] [if exp] [in range] [weight] [, { sum | percent }
                 format(%fmt) gap(relativesize)
                 plabelsubopts(plabel_suboptions) graph_pie_options ]

    aweights, fweights, and pweights are allowed; see weight.


Description 

    pieplot plots pie charts of categorical frequencies.

    pieplot yvar plots a pie chart showing the relative frequencies of the
    distinct values of yvar.

    pieplot yvar xvar plots a set of pie charts showing the relative
    frequencies of the distinct values of yvar for each distinct value of
    xvar.

    Typically, but not necessarily, yvar will be a response or outcome or
    dependent variable, and xvar, whenever specified, will be an explanatory
    or predictor or independent variable.

    By default pie slices are named according to the categories of yvar. See
    also the sum and percent options.

    As an aid to learning the syntax of the ultimately more flexible command
    graph pie, the syntax used to call graph pie is echoed to the Results
    window by pieplot.


Remarks 

    This command is a convenience command providing an alternative to graph
    pie, over() for pie charts showing categorical frequencies.

    graph pie supports three syntaxes. The first two are for calculating pie
    charts from sums of supplied variables and are not of concern here. The
    third is for counting observations in different categories. pieplot
    offers an alternative syntax to this third syntax of graph pie.

    A disadvantage of this third syntax is that it is unlike any other graph
    syntax in that no variable list is expected. In addition, it is unlike
    other syntax that users may issue with categorical variables.  Thus users
    must switch between (say) tabulate yvar and graph pie, over(yvar) or
    tabulate yvar xvar and graph pie, over(yvar) by(xvar).  pieplot is thus
    offered as a bridge to ease learning of the third syntax of graph pie.

    A limitation of pieplot is that it does not offer complete control of the
    presentation of individual pie slice labels. Users desiring such control
    are encouraged to consider use of the Graph Editor or to switch to graph
    pie, as appropriate.


Options 
 
    sum specifies that pie slices show sums, typically the number of
        observations in each category, or more generally the sum of weights
        in each category. The default is to show names of categories on each
        slice.

    percent specifies that pie slices show percents, typically the percent of
        observations in each category, or more generally the percent of the
        total weight in each category. The default is to show names of
        categories on each slice.

        Only one of sum and percent may be specified.

    format(%fmt) specifies a numeric format controlling the presentation of
        sums or percents on all slices.

    gap(relativesize) specifies additional radial distances affecting all
        slices.

    plabelsubopts() may be used to specify additional suboptions of graph
        pie, plabel() affecting all slices.

    graph_pie_options are options of graph pie other than plabel(), over()
        and by().


Examples

    . sysuse auto, clear
    . pieplot rep78
    . pieplot rep78 foreign
    . pieplot rep78 foreign, sum
    . pieplot rep78 foreign, sum plabelsubopts(size(*2))
    . pieplot rep78 foreign, sum plabelsubopts(size(*2)) pie(1, color(red*2))
        pie(2, color(red)) pie(3, color(red*0.7)) pie(4, color(red*0.5))
        pie(5, color(red*0.3)) legend(row(1))


Author

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


Also see

    On-line:  help for graph pie