EVOLUTION-MANAGER
Edit File: SSfol.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>R: Self-Starting Nls First-order Compartment Model</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="R.css" /> </head><body> <table width="100%" summary="page for SSfol {stats}"><tr><td>SSfol {stats}</td><td style="text-align: right;">R Documentation</td></tr></table> <h2>Self-Starting Nls First-order Compartment Model</h2> <h3>Description</h3> <p>This <code>selfStart</code> model evaluates the first-order compartment function and its gradient. It has an <code>initial</code> attribute that creates initial estimates of the parameters <code>lKe</code>, <code>lKa</code>, and <code>lCl</code>. </p> <h3>Usage</h3> <pre> SSfol(Dose, input, lKe, lKa, lCl) </pre> <h3>Arguments</h3> <table summary="R argblock"> <tr valign="top"><td><code>Dose</code></td> <td> <p>a numeric value representing the initial dose.</p> </td></tr> <tr valign="top"><td><code>input</code></td> <td> <p>a numeric vector at which to evaluate the model.</p> </td></tr> <tr valign="top"><td><code>lKe</code></td> <td> <p>a numeric parameter representing the natural logarithm of the elimination rate constant.</p> </td></tr> <tr valign="top"><td><code>lKa</code></td> <td> <p>a numeric parameter representing the natural logarithm of the absorption rate constant.</p> </td></tr> <tr valign="top"><td><code>lCl</code></td> <td> <p>a numeric parameter representing the natural logarithm of the clearance.</p> </td></tr> </table> <h3>Value</h3> <p>a numeric vector of the same length as <code>input</code>, which is the value of the expression </p> <pre>Dose * exp(lKe+lKa-lCl) * (exp(-exp(lKe)*input) - exp(-exp(lKa)*input)) / (exp(lKa) - exp(lKe)) </pre> <p>If all of the arguments <code>lKe</code>, <code>lKa</code>, and <code>lCl</code> are names of objects, the gradient matrix with respect to these names is attached as an attribute named <code>gradient</code>. </p> <h3>Author(s)</h3> <p>José Pinheiro and Douglas Bates</p> <h3>See Also</h3> <p><code><a href="nls.html">nls</a></code>, <code><a href="selfStart.html">selfStart</a></code> </p> <h3>Examples</h3> <pre> Theoph.1 <- Theoph[ Theoph$Subject == 1, ] with(Theoph.1, SSfol(Dose, Time, -2.5, 0.5, -3)) # response only with(Theoph.1, local({ lKe <- -2.5; lKa <- 0.5; lCl <- -3 SSfol(Dose, Time, lKe, lKa, lCl) # response _and_ gradient })) getInitial(conc ~ SSfol(Dose, Time, lKe, lKa, lCl), data = Theoph.1) ## Initial values are in fact the converged values fm1 <- nls(conc ~ SSfol(Dose, Time, lKe, lKa, lCl), data = Theoph.1) summary(fm1) </pre> <hr /><div style="text-align: center;">[Package <em>stats</em> version 3.6.0 <a href="00Index.html">Index</a>]</div> </body></html>