[R] Nonlinear regression

Timothy Axberg axbergtimothy at gmail.com
Wed Dec 20 01:28:00 CET 2017


Should I repost the question with reply-all?

On Tue, Dec 19, 2017 at 6:13 PM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us>
wrote:

> You also need to reply-all so the mailing list stays in the loop.
> --
> Sent from my phone. Please excuse my brevity.
>
> On December 19, 2017 4:00:29 PM PST, Timothy Axberg <
> axbergtimothy at gmail.com> wrote:
> >Sorry about that. Here is the code typed directly on the email.
> >
> >qe = (Qmax * Kl * ce) / (1 + Kl * ce)
> >
> >##The data
> >ce <- c(15.17, 42.15, 69.12, 237.7, 419.77)
> >qe <- c(17.65, 30.07, 65.36, 81.7, 90.2)
> >
> >##The linearized data
> >celin <- 1/ce
> >qelin <- 1/qe
> >
> >plot(ce, qe, xlim = xlim, ylim = ylim)
> >
> >##The linear model
> >fit1 <- lm(qelin ~ celin)
> >intercept1 <- fit1$coefficients[1]
> >slope1 <- fit1$coeffecients[2]
> >summary(fit1)
> >
> >Qmax <- 1/intercept1
> >Kl <- .735011*Qmax
> >
> >xlim <- range(ce, celin)
> >ylim <- range(qe, qelin)
> >
> >abline(lm(qelin ~ celin))
> >
> >c <- seq(min(ce), max(ce))
> >q <- (Qmax*Kl*c)/(1+(Kl*c))
> >
> >lines(c, q)
> >
> >
> >##My attempt at the nonlinear regression
> >fit2 <- nls(qe ~ ((Qmax*Kl*ce)/(1+(Kl*ce))), start = list(Qmax = Qmax,
> >Kl =
> >Kl))
> >results <- fit2$m$getpars()
> >Qmax2 <- fit2$m$getpars()[1]
> >Kl2 <- fit2$m$getpars()[2]
> >summary(fit2)
> >
> >-Timothy
>

	[[alternative HTML version deleted]]



More information about the R-help mailing list