tinfcn.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}
{* 07apr2005}{...}
{cmd:help tinfcn}
{hline}

{title:Title}

{p2colset 5 42 47 2}{...}
{p2col :{hi:[U] 24.3.8 Selecting periods of time}}{hline 2}
{cmd:tin()} and {cmd:twithin()} functions:  Selecting time-spans{p_end}

{title:Syntax}

	{cmd:tin(}[{it:constant}]{cmd:,} [{it:constant}]{cmd:)}

	{cmd:twithin(}[{it:constant}]{cmd:,} [{it:constant}]{cmd:)}

{pstd}
where {it:constant} is a date constant such as {hi:01jan1995} or
{hi:2002-2}, the format being determined by how the data are {cmd:tsset}.


{title:Description}

    Function description:

{p 4 21 2}1st argument:  date constant or nothing; lower bound of range{p_end}
{p 4 21 2}2nd argument:  date constant or nothing; upper bound of range{p_end}
{p 4 21 2}Returns: {space 5} 1 or 0 (meaning True or False)


{pstd}
{cmd:tin()} and {cmd:twithin()} are for use with time-series data.  You
must {cmd:tsset} your data before using these functions; see {helpb tsset}.

{pstd}
{cmd:tin()} returns true if the time variable previously {cmd:tsset} is in
the range specified, which specified range is interpreted as including the
end points.

{pstd}
{cmd:twithin()} returns true if the time variable previously {cmd:tsset} is
within the range specified, which specified range is interpreted as excluding
the end points.


{title:Examples}

{phang}{cmd:. regress} {it:...} {cmd:if tin(1jan1995,31dec1999)}{p_end}
{phang}{cmd:. regress} {it:...} {cmd:if tin(1jan1995,)}{p_end}
{phang}{cmd:. regress} {it:...} {cmd:if tin(,31dec1999)}{p_end}
{phang}{cmd:. regress} {it:...} {cmd:if twithin(,1jan2000)}

{phang}{cmd:. regress} {it:...} {cmd:if tin(1980-1, 1995-4)}{p_end}
{phang}{cmd:. regress} {it:...} {cmd:if tin(1980-1,)}{p_end}
{phang}{cmd:. regress} {it:...} {cmd:if tin(,1995-4)}


{title:Also see}

{psee}
Manual:  {bf:[D] functions},{break}
{bf:[U] 24 Dealing with dates},{break}
{bf:[U] 24.3.8 Selecting periods of time}

{psee}
Online:  {help tdates},
{help tfmt},
{helpb tsset};
{help dates},
{helpb format},
{help functions},
{help tfcn}
{p_end}