separate.hlp

是一个经济学管理应用软件 很难找的 但是经济学学生又必须用到

{smcl}
{* 20jan2005}{...}
{cmd:help separate}{right:dialog:  {bf:{dialog separate}}}
{hline}

{title:Title}

{p2colset 5 21 22 2}{...}
{p2col :{hi:[D] separate} {hline 2}}Create separate variables{p_end}
{p2colreset}{...}


{title:Syntax}

{p 8 25 2}
{cmd:separate}
{varname}
{ifin}
{cmd:,} {cmd:by(}{it:byvar}{c |}{it:exp}{cmd:)}
[{it:options}]

{synoptset 22 tabbed}{...}
{synopthdr}
{synoptline}
{syntab :Main}
{p2coldent :* {opt by(byvar)}}
categorize observations into groups defined by {it:byvar}{p_end}
{p2coldent :* {opth by(exp)}}
categorize observations into two groups defined by {it:exp}{p_end}

{syntab :Options}
{synopt :{opt g:enerate(stubname)}}name new variables by suffixing values to
{it:stubname}; default is to use {varname} as prefix{p_end}
{synopt :{opt seq:uential}}use as name suffix categories numbered sequentially
from 1{p_end}
{synopt :{opt miss:ing}}create variables for the missing values{p_end}
{synopt :{opt short:label}}create shorter variable labels{p_end}
{synoptline}
{p2colreset}{...}
{p 4 6 2}* Either {opt by(byvar)} or {opt by(exp)} must be specified.{p_end}


{title:Description}

{pstd}
{opt separate} creates new variables containing values from {varname}.


{title:Options}

{dlgtab:Main}

{phang}
{cmd:by(}{it:byvar}|{it:exp}{cmd:)}
specifies a single variable defining the categories or a logical expression
that categorizes the observations into two groups.

{pmore}
If {opt by(byvar)} is specified, {it:byvar} may be a numeric
or string variable taking on any values.

{pmore}
If {opth by(exp)} is specified, the expression must evaluate
to true (1), false (0), or missing.

{pmore}
{opt by()} is required.

{dlgtab:Options}

{phang}
{opt generate(stubname)} specifies how the new variables are to be named. If
    {opt generate()} is not specified, {opt separate} uses the name of the
    original variable, shortening it if necessary.  If {opt generate()} is
    specified, {opt separate} uses {it:stubname}.  If any of the resulting
    names is too long when the values are suffixed, it is not shortened and an
    error message is issued.

{phang}
{opt sequential} specifies that categories be numbered sequentially from 1.
    By default, {opt separate} uses the actual values recorded in the original
    variable, if possible, and sequential numbers, otherwise.  {opt separate}
    can use the original values if they are all non-negative integers smaller
    than 10,000.

{phang}
{opt missing} additionally creates a variable for the category missing
    if missing occurs ({it:byvar} takes on the value missing or {it:exp}
    evaluates to missing).  The resulting variable is named in the usual
    manner but with an appended underscore; e.g., {cmd:bp_}.  By default,
    {opt separate} creates no such variable.  Note that the contents of other
    variables are unaffected by whether {opt missing} is specified.

{phang}
{opt shortlabel} causes the creation of a variable label that is shorter than
    the default.


{title:Examples}

{phang}{cmd:. separate mpg, by(foreign)}{p_end}
{phang}{cmd:. qqplot mpg0 mpg1}{p_end}

{phang}{cmd:. separate mpg, by(price>6000) gen(mpgpr)}{p_end}
{phang}{cmd:. qqplot mpgpr0 mpgpr1}{p_end}


{title:Also see}

{psee}
Manual:  {bf:[D] separate}

{psee}
Online:  {helpb tabulate}
{p_end}