similar to: nls minimum factor error

Hi R experts, I'm trying to use nls() for a piecewise linear regression with the first slope constrained to 0. There are 10 data points and when it does converge the second slope is almost always over estimated for some reason. I have many sets of these 10-point datasets that I need to do. The following segment of code is an example, and sorry for the overly precise numbers, they are just

I want to fit discrete data that was measured on a wavegenerator. In this minimal example i generate some artificial data: testsin <- 2+ 5 * sin(1:100) #generate sin data testsin <- testsin+ rnorm(length(testsin), sd = 0.01) #add noise mydata <- list(X=1:100, Y=testsin) # generate mydata object nlmod <- nls(X ~ A+B*sin(C* Y), data=mydata, start=list(A=2, B=4, C=1), trace=TRUE) #

Hello there, I am trying to use R function NLS to analyze my data and one of the examples in the documentation is - ## the nls() internal cheap guess for starting values can be sufficient: x <- -(1:100)/10 y <- 100 + 10 * exp(x / 2) + rnorm(x)/10 nlmod <- nls(y ~ Const + A * exp(B * x), trace=TRUE) plot(x,y, main = "nls(*), data, true function and fit, n=100") curve(100 +

Greets, I'm trying to learn to use nls and was running the example code for an exponential model: > x <- -(1:100)/10 > y <- 100 + 10 * exp(x / 2) + rnorm(x)/10 > nlmod <- nls(y ~ Const + A * exp(B * x)) Error in B * x : non-numeric argument to binary operator In addition: Warning message: In nls(y ~ Const + A * exp(B * x)) : No starting values specified for some

Hello Is there any function to calculate White's standard errors in R in an NLS regression. The sandwich and car package do it but they need an lm object to calculate the error's. Does anyone have idea how to do it for an NLS object ? Regards The woods are lovely, dark and deep But I have promises to keep And miles before I go to sleep And miles before I go to sleep ----- [[alternative

Le 31/05/2017 ? 17:30, Serguei Sokol a ?crit : > > More thorough reading revealed that I have overlooked this phrase in the > line's doc: "left and right /thirds/ of the data" (emphasis is mine). Oops. I have read the first ref returned by google and it happened to be tibco's doc, not the R's one. The layout is very similar hence my mistake. The latter does not

All: Are there any functions out there for selecting all the points in a region of a plot. I envision something like the identify() function except one could circle a cloud of points (and perhaps a vector would be returned of the same length as the points plotted indicating logical membership in the circled cloud). Perhaps someone has done something with the locator() function that would

Seriously, if a method gives a wrong result, it's wrong. line() does NOT implement the algorithm of Tukey, even not after the patch. We're not discussing Excel here, are we? The method of Tukey is rather clear, and it is NOT using the default quantile definition from the quantile function. Actually, it doesn't even use quantiles to define the groups. It just says that the groups

Hi folks I wonder if anyone can help me. I want to run some simulations to see how big a sample size might be necessary to distinguish a curved bivariate relationship (e.g. something that might be best described by a quadratic model) from a relationship that is two straight lines with a sudden change in slope (e.g. something best described by a breakpoint regression). I am using

Estimada Patricia: El mail con spam ha salido de mi casilla, pero yo no lo he enviado intencionalmente. Algo o alguien habrá robado mi lista de contactos y envió este mail  en forma masiva a todos ellos. Pido disculpas por las molestias ocasionadas y te pido por favor que tengas en cuenta este punto para futuras eventualidades, porque a cualquiera le puede pasar.   Saludos! Cesar Procopio.

Yeh, I eventually figured that out. Thanks for responding though. Jack ________________________________________ From: llvmdev-bounces at cs.uiuc.edu [llvmdev-bounces at cs.uiuc.edu] on behalf of llvmdev-request at cs.uiuc.edu [llvmdev-request at cs.uiuc.edu] Sent: Sunday, November 20, 2011 10:00 AM To: llvmdev at cs.uiuc.edu Subject: LLVMdev Digest, Vol 89, Issue 47 Send LLVMdev mailing list