sorry, I don't get it... On Wed, Mar 17, 2021 at 2:35 PM Duncan Murdoch <murdoch.dun...@gmail.com> wrote: > > On 17/03/2021 6:59 a.m., Luigi Marongiu wrote: > > yes, but in `rutledge` I model y as `y = (M / ( 1 + exp(-(x-m)/s)) ) + > > B`, with x being 1:45. Isn't that the equivalent of what I fed Desmos > > with? Tx > > No, it's not. > > Duncan Murdoch > > > > > On Wed, Mar 17, 2021 at 11:31 AM Duncan Murdoch > > <murdoch.dun...@gmail.com> wrote: > >> > >> On 17/03/2021 5:41 a.m., Luigi Marongiu wrote: > >>> Hello, > >>> I have a dataset from a polymerase chain reaction. I am using the > >>> equation given by Rutledge > >>> (https://pubmed.ncbi.nlm.nih.gov/15601990/) but the profile I get in R > >>> does not match the data. I ran the same thing in Desmos and instead > >>> the profile is correct (attached). > >>> Why do I not get the same matching model as in Desmos? I believe the > >>> formula in R is the same as the one in Desmos, and I am using the same > >>> parameters. > >>> Is there a procedure to debug models? > >>> Thanks > >>> > >>> Here is the code: > >>> ``` > >>> high <- c(120.64, 66.14, 34.87, 27.11, 8.87, -5.8, 4.52, -7.16, -17.39, > >>> -14.29, -20.26, -14.99, -21.05, -20.64, -8.03, -21.56, -1.28, > >>> 15.01, > >>> 75.26, 191.76, 455.09, 985.96, 1825.59, 2908.08, 3993.18, > >>> 5059.94, > >>> 6071.93, 6986.32, 7796.01, 8502.25, 9111.46, 9638.01, 10077.19, > >>> 10452.02, 10751.81, 11017.49, 11240.37, 11427.47, 11570.07, > >>> 11684.96, > >>> 11781.77, 11863.35, 11927.44, 11980.81, 12021.88) > >>> plot(1:45, high, type = "l") > >>> rutledge <- function(p, x) { > >>> m = p$half_fluorescence > >>> s = p$slope > >>> M = p$max_fluorescence > >>> B = p$back_fluorescence > >>> y = (M / ( 1 + exp(-(x-m)/s)) ) + B > >>> return(y) > >>> } > >>> desmos <- rutledge(list(half_fluorescence = 27.1102, slope = 2.76798, > >>> max_fluorescence = 11839.8, back_fluorescence > >>> = -138.864) , high) > >>> > >>> points(1:45, desmos, type="l", col="blue") > >> > >> > >> In your calculation of desmos, you are using the Y variable for x in the > >> formula. Calculate it this way instead: > >> > >> desmos <- rutledge(list(half_fluorescence = 27.1102, slope = 2.76798, > >> max_fluorescence = 11839.8, back_fluorescence > >> = -138.864) , 1:45) > >> > >> Duncan Murdoch > >> > > > > >
-- Best regards, Luigi ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.