creturn.hlp

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    change with the by-group; {cmd:_N} does.

{pmore}
  The advantage of {cmd:c(N)} is in nonexpression contexts.  Say that you are
  calling a subroutine, {cmd:mysub}, which takes as an argument the number of
  observations in the dataset.  In that case, you could code

	    {cmd:local nobs = _N}
	    {cmd:mysub `nobs'}
	or
	    {cmd:mysub `c(N)'}

{pin2}
    The second requires less typing.

{phang}
{cmd:c(k)} returns a numeric scalar equal to the number of variables
    in the dataset in memory.
    {cmd:c(k)} is equal to {cmd:r(k)} returned by {helpb describe}.

{phang}
{cmd:c(width)} returns a numeric scalar equal to the width, in bytes,
    of the dataset in memory.
    If you had a dataset with 2 {help int} variables, 3
    {help float}s, 1 {help double}, and a {help data types:str20} variable, the
    width of the dataset would be 2*2 + 3*4 + 8 + 20 = 44 bytes.
    {cmd:c(width)} is equal to {cmd:r(width)} returned by {helpb describe}.

{phang}
{cmd:c(changed)} returns a numeric scalar equal to 0 if the dataset in memory
    has not changed since it was last saved and returns 1 otherwise.
    {cmd:c(changed)} is equal to {cmd:r(changed)} returned by {helpb describe}.

{phang}
{cmd:c(filename)} returns a string containing the filename last specified with
    a {helpb use} or {helpb save}, such as
    "{cmd:http://www.stata-press.com/data/r9/auto.dta}".  {cmd:c(filename)} is
    equal to {cmd:$S_FN}.

{phang}
{cmd:c(filedate)} returns a string containing the date and time the file in
    {cmd:c(filename)} was last saved, such as "{cmd:7 Jul 2002 13:51}".
    {cmd:c(filedate)} is equal to {cmd:$S_FNDATE}.


{title:Output settings}

{phang}
{cmd:c(more)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb more:set more} setting.

{phang}
{cmd:c(rmsg)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb rmsg:set rmsg} setting.

{phang}
{cmd:c(dp)} returns a string containing "{cmd:period}" or "{cmd:comma}"
    indicating the current {helpb dp:set dp} setting.

{phang}
{cmd:c(linesize)} returns a numeric scalar equal to the current
    {helpb linesize:set linesize} setting.

{phang}
{cmd:c(pagesize)} returns a numeric scalar equal to the current
    {helpb pagesize:set pagesize} setting.

{phang}
{cmd:c(logtype)} returns a string containing "{cmd:smcl}" or "{cmd:text}"
    indicating the current {helpb logtype:set logtype} setting.


{title:Interface settings}

{phang}
{cmd:c(dockable)} (Windows only) returns a string containing "{cmd:on}" or
    "{cmd:off}" indicating the current {helpb dockable:set dockable} setting.

{phang}
{cmd:c(dockingguides)} (Windows only) returns a string containing "{cmd:on}" or
    "{cmd:off}" indicating the current
    {helpb dockingguides:set dockingguides} setting.

{phang}
{cmd:c(floatresults)} (Windows only) returns a string containing "{cmd:on}" or
    "{cmd:off}" indicating the current {helpb floatresults:set floatresults} 
    setting.

{phang}
{cmd:c(floatwindows)} (Windows only) returns a string containing "{cmd:on}" or
    "{cmd:off}" indicating the current {helpb floatwindows:set floatwindows} 
    setting.

{phang}
{cmd:c(locksplitters)} (Windows only) returns a string containing "{cmd:on}" or
    "{cmd:off}" indicating the current
    {helpb locksplitters:set locksplitters} setting.

{phang}
{cmd:c(xptheme)} (Windows only) returns a string containing "{cmd:on}" or
    "{cmd:off}", indicating the current {helpb xptheme:set xptheme} setting.

{phang}
{cmd:c(linegap)} returns a numeric scalar equal to the current
    {helpb linegap:set linegap} setting.  If {cmd:set linegap} is
    irrelevant under the version of Stata that is running,
    {cmd:c(linegap)} returns a system missing value.

{phang}
{cmd:c(scrollbufsize)} returns a numeric scalar equal to the current
    {helpb scrollbufsize:set scrollbufsize} setting.  If
    {cmd:set scrollbufsize} is irrelevant under the version of Stata you
    are running, {cmd:c(scrollbufsize)} returns a system missing value.

{phang}
{cmd:c(varlabelpos)} returns a numeric scalar equal to the current
    {helpb varlabelpos:set varlabelpos} setting.  If
    {cmd:set varlabelpos} is irrelevant under the version of Stata you
    are running, {cmd:c(varlabelpos)} returns a system missing value.

{phang}
{cmd:c(reventries)} (Windows only) returns a numeric scalar containing the
    maximum number of commands stored by the Review window; see 
    {helpb reventries}.

{phang}
{cmd:c(maxdb)} returns a numeric scalar containing the maximum number of
    dialog boxes whose contents are remembered from one invocation to the
    next during a session; see {helpb db}.

{phang}
{cmd:c(smalldlg)} (Windows 98 and ME only) returns a string containing
    "{cmd:on}" or "{cmd:off}" indicating the current
    {helpb smalldlg:set smalldlg} setting.


{title:Graphics settings}

{phang}
{cmd:c(graphics)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb set_graphics:set graphics} setting.

{phang}
{cmd:c(scheme)} returns the name of the current {helpb set scheme}.

{phang}
{cmd:c(printcolor)} returns "{cmd:automatic}", "{cmd:asis}",
    "{cmd:gs1}", "{cmd:gs2}", or "{cmd:gs3}" indicating the current
    {helpb set printcolor} setting.


{title:Efficiency settings}

{phang}
{cmd:c(adosize)} returns a numeric scalar equal to the current
    {helpb adosize:set adosize} setting.

{phang}
{cmd:c(virtual)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb virtual:set virtual} setting.


{title:Mata settings}

{phang}
{cmd:c(matastrict)}
 returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb matastrict:set matastrict} setting.

{phang}
{cmd:c(matalnum)}
 returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb matalnum:set matalnum} setting.

{phang}
{cmd:c(mataoptimize}
 returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb mataoptimize:set mataoptimize} setting.

{phang}
{cmd:c(matafavor)}
 returns a string containing "{cmd:space}" or "{cmd:speed}"
    indicating the current {helpb matafavor:set matafavor} setting.

{phang}
{cmd:c(matacache)}
 returns a numeric scalar containing the maximum amount of memory, in
 kilobytes, that may be consumed before Mata starts looking to drop autoloaded
 functions that are not currently being used.

{phang}
{cmd:c(matalibs)}
 returns a string containing the names and order of the {cmd:.mlib} libraries
 to be searched; see {help m1_how:[M-1] how}.

{phang}
{cmd:c(matamofirst)}
 returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb matamofirst:set matamofirst} setting.


{title:Network settings}

{phang}
{cmd:c(checksum)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb checksum:set checksum} setting.

{phang}
{cmd:c(timeout1)} returns a numeric scalar equal to the current
    {helpb timeout1:set timeout1} setting.

{phang}
{cmd:c(timeout2)} returns a numeric scalar equal to the current
    {helpb timeout2:set timeout2} setting.

{phang}
{cmd:c(httpproxy)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb httpproxy:set httpproxy} setting.

{phang}
{cmd:c(httpproxyhost)} returns a string containing the name of the
    proxy host or {cmd:""} if no proxy host is set.
    {cmd:c(httpproxyhost)} is relevant only if {cmd:c(httpproxy)}=="{cmd:on}".

{phang}
{cmd:c(httpproxyport)} returns a numeric scalar equal to the proxy port number.
    {cmd:c(httpproxyport)} is relevant only if {cmd:c(httpproxy)}=="{cmd:on}".

{phang}
{cmd:c(httpproxyauth)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb httpproxy:set httpproxyauth} setting.
    {cmd:c(httpproxyauth)} is relevant only if {cmd:c(httpproxy)}=="{cmd:on}".

{phang}
{cmd:c(httpproxyuser)} returns a string containing the name of the proxy
    user or {cmd:""} if no proxy user is set.
    {cmd:c(httpproxyuser)} is relevant only if
    {cmd:c(httpproxyauth)}=="{cmd:on}" and {cmd:c(httpproxy)}=="{cmd:on}".

{phang}
{cmd:c(httpproxypw)} returns a string containing "{cmd:*}" if a password
    is set or {cmd:""} otherwise.
    {cmd:c(httpproxypw)} is relevant only if
    {cmd:c(httpproxyauth)}=="{cmd:on}" and {cmd:c(httpproxy)}=="{cmd:on}".


{title:Update settings}

{phang}
{cmd:c(update_query)} (Windows and Macintosh only) returns a string containing
    "{cmd:on}" or "{cmd:off}" indicating the current
    {helpb update_query:set update_query} setting.

{phang}
{cmd:c(update_interval)} (Windows and Macintosh only) returns a numeric scalar
    containing the current {helpb update_interval:set update_interval} setting.

{phang}
{cmd:c(update_prompt)} (Windows and Macintosh only) returns a string containing
    "{cmd:on}" or "{cmd:off}" indicating the current
    {helpb update_prompt:set update_prompt} setting.


{title:Trace (program debugging) settings}

{phang}
{cmd:c(trace)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb trace:set trace} setting.

{phang}
{cmd:c(tracedepth)} returns a numeric scalar reporting the current
    {helpb trace:set tracedepth} setting.

{phang}
{cmd:c(tracesep)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb trace:set tracesep} setting.

{phang}
{cmd:c(traceindent)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb trace:set traceindent} setting.

{phang}
{cmd:c(traceexpand)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb trace:set traceexpand} setting.

{phang}
{cmd:c(tracenumber)} returns a string containing "{cmd:on}" or "{cmd:off}"
    indicating the current {helpb trace:set tracenumber} setting.

{phang}
{cmd:c(tracehilite)} returns a string containing "{it:pattern}"
    indicating the current {helpb trace:set tracehilite} setting.


{title:Other settings}

{phang}
{cmd:c(type)} returns a string containing "{cmd:float}" or "{cmd:double}"
    indicating the current {helpb generate:set type} setting.

{phang}
{cmd:c(level)} returns a numeric scalar equal to the current
    {helpb level:set level} setting.

{phang}
{cmd:c(maxiter)} returns a numeric scalar equal to the current 
{helpb maxiter:set maxiter} setting.

{phang}
{cmd:c(searchdefault)} returns a string containing "{cmd:local}", "{cmd:net}",
    or "{cmd:all}" indicating the current {helpb search:set searchdefault}
    setting.

{phang}
{cmd:c(seed)} returns a string containing the current {helpb seed:set seed}
    setting.  This records the current state of the random-number generator
    {helpb random:uniform()}.

{phang}
{cmd:c(varabbrev)} returns a string containing "{cmd:on}" or "{cmd:off}"
indicating the current {helpb varabbrev:set varabbrev} setting.


{title:Other}

{phang}
{cmd:c(pi)} returns a numeric scalar equal to {cmd:_pi}, the value of the
    ratio of the circumference to the diameter of a circle.  In an expression,
    it makes no difference whether you use {cmd:c(pi)} or {cmd:_pi}.
    {cmd:c(pi)}, however, may be used (enclosed in single quotes) in other
    contexts.

{phang}
{cmd:c(alpha)} returns a string containing the space-separated list of the
    lowercase letters.

{phang}
{cmd:c(ALPHA)} returns a string containing the space-separated list of the
    uppercase letters.

{phang}
{cmd:c(Mons)} returns a string containing the space-separated list of month
    names abbreviated to three characters.

{phang}
{cmd:c(Months)} returns a string containing the space-separated list of month
    names.

{phang}
{cmd:c(Wdays)} returns a string containing the space-separated list of weekday
    names abbreviated to three characters.

{phang}
{cmd:c(Weekdays)} returns a string containing the space-separated list of
    weekday names.

{phang}
{cmd:c(rc)} returns a numeric scalar equal to {cmd:_rc}, the value set by
    the {helpb capture} command.  In an expression, it makes no difference
    whether you use {cmd:c(rc)} or {cmd:_rc}.  {cmd:c(rc)}, however, may be
    used (enclosed in single quotes) in other contexts.  This is less important
    than it sounds because you could just as easily type {cmd:`=_rc'}.


{title:Also see}

{psee}Manual:  {bf:[P] creturn}

{psee}
Online:  
{helpb query},
{helpb return},
{help _variables}
{p_end}