post.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}
{* 09feb2005}{...}
{cmd:help postfile}, {cmd:help post}, {cmd:help postclose}, {cmd:help postutil}
{hline}

{title:Title}

{p2colset 5 21 23 2}{...}
{p2col :{hi:[P] postfile} {hline 2}}Save results in Stata dataset{p_end}
{p2colreset}{...}


{title:Syntax}

{p 8 17 2}{cmd:postfile}{space 2}{it:postname} {it:newvarlist} {cmd:using}
{it:filename} [{cmd:,} {cmdab:e:very:(}{it:#}{cmd:)} {cmd:replace}]

{p 8 17 2}{cmd:post}{space 6}{it:postname} {cmd:(}{it:exp}{cmd:)}
{cmd:(}{it:exp}{cmd:)} {it:...} {cmd:(}{it:exp}{cmd:)}

	{cmd:postclose} {it:postname}

	{cmd:postutil  dir}

	{cmd:postutil  clear}


{title:Description}

{pstd}
These commands are utilities to assist Stata programmers in performing
Monte Carlo-type experiments.

{pstd}
{cmd:postfile} declares the variable names and the filename of a (new) Stata
dataset where results are to be stored.  Storage types may be specified with
{it:newvarlist}; for example,

{pin}
	{cmd:. postfile myhandle a b str20 c double(d e f) using myfile}

{pstd}
{cmd:post} adds a new observation to the declared dataset.

{pstd}
{cmd:postclose} declares an end to the posting of observations.  After
{cmd:postclose}, the new dataset contains the posted results and may be loaded
using {cmd:use}; see {helpb use}.

{pstd}
{cmd:postutil dir} lists all open postfiles.  {cmd:postutil clear} closes
all open postfiles.

{pstd}
All five commands manipulate the new dataset without disturbing the data in
memory.


{title:Options}

{phang}{cmd:every(}{it:#}{cmd:)} specifies results are to be written to disk
every {it:#}th call to {cmd:post}.  {cmd:post} temporarily holds results in
memory and periodically opens the dataset being built to append to the stored
results.  {cmd:every()} should typically not be specified, as you are unlikely
to choose a value for {it:#} that is as efficient as the number {cmd:post}
chooses on its own, which is a function of the number of results being written
and their storage type.

{phang}{cmd:replace} indicates that the file specified may already exist,
and, if it does, {cmd:postfile} may erase the file and create a new one.


{title:Remarks}

{pstd}
Typical use of the post commands is

	{cmd:tempname memhold}
	{cmd:tempfile results}
	{it:...}
	{cmd:postfile `memhold'} {it:...} {cmd:using `results'}
	{it:...}
	{cmd:while} {it:...} {cmd:{c -(}}
		{it:...}
		{cmd:post `memhold'} {it:...}
		{it:...}
	{cmd:{c )-}}
	{cmd:postclose `memhold'}
	{it:...}


{title:Also see}

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

{psee}
Online:  {helpb bootstrap}, {helpb simulate}
{p_end}