similar to: nls question

Is there any simple way of reading dates from a file? I'm currently reading dates in as characters and then converting them to POSIXlt objects. However I would like to know if there is a way of having read.table or scan convert a field to a date-time class. -- ------------------------------------------------------------------ Suchandra S. Thapa s-thapa-11 at alumni.uchicago.edu

Thanks to Peter Dalgaard and Suchandra Thapa for answering my question! Before I settle on a particular option, I'd like to ask one more question if I may: Are there any practical advantages to compiling R to 64-bit vs 32-bit? Regards, Andy > -----Original Message----- > From: Peter Dalgaard BSA [mailto:p.dalgaard at biostat.ku.dk] > Sent: Thursday, April 18, 2002 4:19 PM > To:

Hi, df <- read.table("data.txt", header=T); library(nls); fm <- nls(y ~ a*(x+d)^(-b), df, start=list(a=max(df->y,na.rm=T)/2,b=1,d=0)); I was using the following routine which was giving Singular Gradient, Error in numericDeriv(form[[3]], names(ind), env) : Missing value or an Infinity produced when evaluating the model errors. I also tried the

I noticed a wierd quirk in telnet on redhat 5.2 that seems to allow others to verify whether an account name exists on a linux machine or not. If you telnet into a machine and use an username that does not exist, you get four attempts before the telnet session is closed. If the username exists then you have three attempts before the session is closed. I know that there are other ways to find

All, I'm trying to install R-base on RedHat Linux 7.2. Rpm complains that libreadline.4.1.so is needed; the problem is that I have libreadline4.2.so. What can I do to get around this? -Scott -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or

(Thanks for answers on my naif dual processor question!). I'm going to compile R-1.4.0 for linux (Suse 7.3) and hesitate at including the gnome interface. Do people that have tried the gnome interface recommend it? How is R started with this interface? If I build with the --with-gnome option, will still have the option of actually not using the interface if I don't find it useful?

Hi, I am a non-expert user of R. I am essaying the fit of two different functions to my data, but I receive two different error messages. I suppose I have two different problems here... But, of which nature? In the first instance I did try with some different starting values for the parameters, but without success. If anyone could suggest a sensible way to proceed to solve these I would be

Hi, I'm trying to fit some data using a logistic function defined as y ~ a * (1+m*exp(-x/tau)) / (1+n*exp(-x/tau) My data is below: x <- 1:100 y <- c(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,1,1,1,2,2,2,2,2,3,4,4,4,5, 5,5,5,6,6,6,6,6,8,8,9,9,10,13,14,16,19,21, 24,28,33,40,42,44,50,54,69,70,93,96,110,127,127,141,157,169,

Hi, I am out of town and will get back to you on the 13th of July. Leo >>> "r-help at stat.math.ethz.ch" 06/27/03 00:32 >>> Send R-help mailing list submissions to r-help at stat.math.ethz.ch To subscribe or unsubscribe via the World Wide Web, visit https://www.stat.math.ethz.ch/mailman/listinfo/r-help or, via email, send a message with subject or body

Dear R-users, I am trying to create a model using the NLS function, such that: Y = f(X) + q + e Where f is a nonlinear (Weibull: a*(1-exp(-b*X^c)) function of X and q is a covariate (continous variable) and e is an error term. I know that you can create multiple nonlinear regressions where x is polynomial for example, but is it possible to do this kind of thing when x is a function with unknown

Hi Everyone, I am trying to use NLS to fit a dataset using a Kappa function, but I am having problems. Depending on the start values that I provide, I get either: Error in numericDeriv(form[[3L]], names(ind), env) : Missing value or an infinity produced when evaluating the model Or Error in nls(FldFatRate ~ funct3(MeanDepth_m, h, k, z, a), data = data1, : singular gradient I think these

Hi! How to write in model's formula of type: nls(y~k/(x^n), data=data, start=list(k=1,n=1)) i.e the problem is on x^n, I(x^n) generate error thanks Jarek

I am writing this email from Wildlife Institute of India, an autonomous institution of Ministry of Environment & Forests, Government of India. Our institute is involved in the research, management and training for the conservation of wildlife in India. We have a GIS and Remote Sensing laboratory having four Sun workstations on Solaris 7 and two Pentium 4 workstations on Windows NT 4.0 are

Hi All. I've run into a problem with the plinear algorithm in nls that is confusing me. Assume the following reaction time data over 15 trials for a single unit. Trials are coded from 0-14 so that the intercept represents reaction time in the first trial. trl RT 0 1132.0 1 630.5 2 1371.5 3 704.0 4 488.5 5 575.5 6 613.0 7 824.5 8 509.0 9

Is there anyway to change any y[i] value (i=2,...6) to make following NLS workable? x <- c(0,5,10,15,20,25,30) y <- c(1.00000,0.82000,0.68000,0.64000,0.66667,0.68667,0.64000) lm(1/y ~~ x) nls(1/y ~~ a+b*x^c, start=list(a=1.16122,b=0.01565,c=1), trace=TRUE) #0.0920573 : 1.16122 0.01565 1.00000 #Error in numericDeriv(form[[3]], names(ind), env) : # Missing value or

Hi list. I''m writing a program that stores a lot of Floats into MySQL database. Simplified version of the program use the following form of class. class Val < ActiveRecord::BASE end And Vals table contains one column: num double One of my data contains -Infinity for num and when I try to Val.new Val.num = <- Here goes -Inifinity Val.save! Then the program crashes:

Hi, I am trying to bootstrap the difference between each parameters among two non linear regression (distributed loss model) as following: # data.frame > Raies[1:10,] Tps SolA Solb 1 0 32.97 35.92 2 0 32.01 31.35 3 1 21.73 22.03 4 1 23.73 18.53 5 2 19.68 18.28 6 2 18.56 16.79 7 3 18.79 15.61 8 3 17.60 13.43 9 4 14.83 12.76 10 4 17.33 14.91 etc... # non

Dear all, I tried to use nls, but I got the following error Error in numericDeriv(form[[3L]], names(ind), env) : Missing value or an infinity produced when evaluating the model Any suggestion? Thanks, Paola. The code I wrote is Data_pp2_mrna <- data.frame( p1 = protein_1, p6 = protein_6, pp2_mrna

I'm trying to find a way to fit a polynomial of degree n in x and y to a set of x, y, and z data that I have and obtain the coefficients for the terms of the fitted polynomial. However, when I try to use the surf.ls function I'm getting odd results. > x <- seq(0, 10, length=50) > y <- x > f <- function (x, y) {x^2 + y} > library(spatial) > test <-

Hello. I am using the nonlinear least squares function (nls). The function that I am trying to fit seems to be very sensitive to the starting values and, if these are not chosen properly, the nls function stops and gives an error message: Error in numericDeriv(form[[3]], names(ind), env) : Missing value or an Infinity produced when evaluating the model In addition: Warning