Thanks. I see what went wrong.
2015-12-07 16:33 GMT-05:00 Jeff Newmiller <jdnew...@dcn.davis.ca.us>: > The fine manual for the drm function mentions a parameter "logDose" ... I > expect that since you did not specify it that the drm function is helpfully > attempting to take the log of your data for you. > > I highly recommend reading up on making reproducible examples so your > helpers can experiment with your problem directly instead of guessing by > reading only. Of course, you would then want to post using plain text as > the Posting Guide indicates so the HTML would not corrupt your code. > > > http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example > -- > Sent from my phone. Please excuse my brevity. > > On December 7, 2015 1:05:32 PM PST, li li <hannah....@gmail.com> wrote: >> >> Hi Jeff, >> I am not sure where the log of 0 was taken? >> Thanks. >> Li >> >> 2015-12-07 15:55 GMT-05:00 Jeff Newmiller <jdnew...@dcn.davis.ca.us>: >> >>> Log of zero is infinity. Don't do that. >>> -- >>> Sent from my phone. Please excuse my brevity. >>> >>> On December 7, 2015 12:15:48 PM PST, li li <hannah....@gmail.com> wrote: >>> >>>> Hi all, >>>> I am trying to use the drm function in drc package to fit a 4 PL or 3PL >>>> curve for an assay response. Please see the listed data below. When I do >>>> the curve fitting, it returns the following error message. Anyone who >>>> familiar with this have any input on what went wrong? >>>> Thanks so much in advance!! >>>> Hanna >>>> >>>> dat >>>>> >>>> values log_dose >>>> 1 -68.1125 3.9120230 >>>> 2 -73.8955 3.9120230 >>>> 3 -75.1235 3.9120230 >>>> 4 -47.3205 3.2188758 >>>> 5 -52.9835 3.2188758 >>>> 6 -58.0075 3.2188758 >>>> 7 8.2515 2.5257286 >>>> 8 -24.5925 2.5257286 >>>> 9 -18.1425 2.5257286 >>>> 10 75.3375 1.8325815 >>>> 11 89.3755 1.8325815 >>>> 12 115.9685 1.8325815 >>>> 13 345.7675 1.1394343 >>>> 14 470.8125 >>>> 1.1394343 >>>> 15 514.8985 1.1394343 >>>> 16 >>>> 1003.2235 0.4462871 >>>> 17 1033.0345 0.4462871 >>>> 18 866.1365 0.4462871 >>>> 19 1383.6525 -0.2468601 >>>> 20 1431.3245 -0.2468601 >>>> 21 1459.8025 -0.2468601 >>>> 22 1852.5795 -0.9400073 >>>> 23 1917.8015 -0.9400073 >>>> 24 1858.0875 -0.9400073 >>>> 25 1995.1185 -1.6331544 >>>> 26 2033.9455 -1.6331544 >>>> 27 1991.0405 -1.6331544 >>>> 28 2064.5855 -2.3263016 >>>> 29 2043.5195 -2.3263016 >>>> 30 2089.8525 -2.3263016 >>>> 31 2147.8445 -3.0194488 >>>> 32 2047.7905 -3.0194488 >>>> 33 2002.5375 -3.0194488 >>>> 34 2075.2665 -3.7125960 >>>> 35 2068.3545 -3.7125960 >>>> 36 2055.9605 -3.7125960 >>>> >>>>> mod1 <- drm(values~log_dose, fct=LL.4(), data=dat) >>>>> >>>> Error in optim(startVec, opfct, hessian = TRUE, method = optMethod, control >>>> = list(maxit = maxIt, : >>>> initial value in 'vmmin' is not >>>> finite >>>> Error in drmOpt(opfct, opdfct1, startVecSc, >>>> optMethod, constrained, >>>> warnVal, : >>>> Convergence failed >>>> >>>>> >>>>> >>>> [[alternative HTML version deleted]] >>>> >>>> ------------------------------ >>>> >>>> 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. >>>> >>>> >> [[alternative HTML version deleted]] ______________________________________________ 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.