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help for pcontract                                               (Roger Newson)
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Make dataset of frequencies and percentages

        pcontract varlist [weight] [if exp] [in range] [, freq(varname)
                 percent(varname) cfreq(varname) cpercent(varname) float
                 format(format) zero nomiss ]

    fweights are allowed; see help weights.


Description

    pcontract is an extended version of contract.  It replaces the dataset in
    memory with a new dataset consisting of all combinations of varlist that
    exist in the data and new variables containing the frequency and
    percentage of each combination, and, optionally, the cumulative frequency
    and percentage of each combination.


Options

    freq(varname) specifies a name for the frequency variable.  If not
        specified, _freq is used. The name must be new.

    percent(varname) specifies a name for the percentage variable.  If not
        specified, _percent is used. The name must be new.

    cfreq(varname) specifies a name for the cumulative frequency variable.
        If not specified, no cumulative frequency variable is created.  The
        name must be new.

    cpercent(varname) specifies a name for the cumulative percentage
        variable.  If not specified, no cumulative percentage variable is
        created.  The name must be new.

    float specifies that the percentage variables specified by percent and
        cpercent will be generated as variables of type float.  If float is
        not specified, then these variables will be generated as variables of
        type double. All generated variables are compressed to the smallest
        storage type possible without loss of precision. See help for 
        compress.

    format(format) specifies a display format for the generated percentage
        variables specified by percent() and cpercent().  If format() is not
        specified, then these variables will have the display format %8.2f.

    zero specifies that combinations with frequency zero are wanted.

    nomiss specifies that observations with missing values on any of the
        variables in varlist will be dropped.  If not specified, all
        observations possible are used.


Examples

    . pcontract foreign rep78
    . pcontract foreign rep78, zero
    . pcontract foreign rep78, f(count) zero nomiss
    . pcontract foreign rep78,fr(frequency) per(percentage) cf(cumfreq)
        cp(cumperc) float format(%4.0f)

    . pcontract _all


Also see

    Manual:  [R] contract, [R] compress, [R] format

    Online:  help for contract, compress, format, expand; collapse,