mf_designmatrix.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}
{* 31mar2005}{...}
{cmd:help mata designmatrix()}
{hline}
{* index design matrix}{...}
{* index designmatrix()}{...}

{title:Title}

{p 4 4 2}
{bf:[M-5] designmatrix() -- Design matrices}


{title:Syntax}

{p 8 12 2}
{it:real matrix}
{cmd:designmatrix(}{it:real colvector v}{cmd:)}


{title:Description}

{p 4 4 2}
{cmd:designmatrix(}{it:v}{cmd:)}
returns a {cmd:rows(}{it:v}{cmd:)}
{it:x}
{cmd:colmax(}{it:v}{cmd:)} matrix with ones in the 
indicated columns and zero everywhere else.


{title:Remarks}

{p 4 4 2}
{cmd:designmatrix((1\2\3))} is equal to {cmd:I(3)}, the 3 {it:x} 3 identity
matrix.


{title:Conformability}

    {cmd:designmatrix(}{it:v}{cmd:)}:
		{it:v}:  {it:r} {it:x} 1
	   {it:result}:  {it:r} {it:x} {cmd:colmax(}{it:v}{cmd:)} (0 {it:x} 0 if {it:r}==0)


{title:Diagnostics}

{p 4 4 2}
{cmd:designmatrix(}{it:v}{cmd:)}
aborts with error if any element of {it:v} is < 1.


{title:Source code}

{p 4 4 2}
{view designmatrix.mata, adopath asis:designmatrix.mata}


{title:Also see}

{p 4 13 2}
Manual:  {hi:[M-5] designmatrix()}

{p 4 13 2}
Online:  help for 
{bf:{help m4_matrix:[M-4] matrix}}
{p_end}