{smcl}
{* 16feb2007}{...}
{.-}
help for {cmd:rcs} 
{.-}

{title:generate restricted cubic spline basis functions}

{p 4 10 4}
{cmd:rcs}
{it:varname}
[{cmd:if}]
[{cmd:in}
,       
{cmdab:k:nots}{cmd:(}{it:numlist}{cmd:)}
[{cmdab:g:en}]{cmd:(}{it:stubname}{cmd:)}
[{cmdab:d:gen}]{cmd:(}{it:stubname}{cmd:)}

{title:Description}

{p}{cmd:rcs} generates basis functions for restricted cubic splines and (optionally) their derivatives. The function is assumed linear beyond the two boundary knots.

{title:Options}

{p 0 4}{cmdab:k:knots}{cmd:(}{it:knots}{cmd:)} list the knots.

{p 0 4}{cmdab:g:en}{cmd:(}{it:stubname}{cmd:)} gives a stubname for the generated cubic splines variables. E.g. {cmd:gen(rcs)} will create variable {it:rcs1, rcs2, ...}

{p 0 4}{cmdab:d:gen}{cmd:(}{it:stubname}{cmd:)} gives a stubname for the  derivatives of the cubic spline variables. If this option is omitted, the 
derivatives are not calculated.

{title:Example:}

{p 4 8 2}{cmd:. rcs x, knots(10 30 50 70 90) gen(rcs)}

{title:Authors}

{p} Chris Nelson ({browse "mailto:cn46@le.ac.uk":cn46@le.ac.uk}) and Paul Lambert ({browse "mailto:paul.lambert@le.ac.uk":paul.lambert@le.ac.uk})  

{title:Also see}

{p 0 19}On-line:  help for {help splinegen}, {help stcurve}