Re: [R] NLS "Singular Gradient" Error

Hi Ben, That's great, thank you very much indeed. Kind regards, Neal Quoting "Ben Bolker [via R]" : > > > > bsnrh leeds.ac.uk> writes: > >> >> >> Hi Ben, >> >> Your book refers to the mle function in the emdbookx package.

Re: [R] NLS "Singular Gradient" Error

Hi Ben, Your book refers to the mle function in the emdbookx package. I was wondering if it's possible to find that package on the internet? Many thanks, Neal -- View this message in context: http://r.789695.n4.nabble.com/NLS-Singular-Gradient-Error-tp2069029p2073544.html Sent from the R help

Re: [R] NLS "Singular Gradient" Error

That's excellent, thank you - precisely what I was looking for. Many thanks indeed. -- View this message in context: http://r.789695.n4.nabble.com/NLS-Singular-Gradient-Error-tp2069029p2073492.html Sent from the R help mailing list archive at Nabble.com.

Re: [R] NLS "Singular Gradient" Error

No success means that I was not successful in changing the outputed error. It had no effect on the model. Thank you for your suggestions; The first returns this error; "Error in lm.fit(x, y, offset = offset, singular.ok = singular.ok, ...) : NA/NaN/Inf in foreign function call (arg 4)" I don

Re: [R] NLS "Singular Gradient" Error

Thank you for your message. This isn't the Rogers equation, although I am not familiar with that particular one. It is from Juliano's (2001) Nonlinear Curve Fitting chapter in Scheiner and Gurevitch. -- View this message in context: http://r.789695.n4.nabble.com/NLS-Singular-Gradient-Error-tp20

Re: [R] NLS "Singular Gradient" Error

Thank you for your reply. The equation is derived from Juliano's chapter in Scheiner and Gurevitch (2001) on Functional Responses. I have tried calling T<-24 and rerunning with no success sadly. -- View this message in context: http://r.789695.n4.nabble.com/NLS-Singular-Gradient-Error-tp206902

[R] NLS "Singular Gradient" Error

Hello, I am trying to model a type II functional response of number of prey eaten (Ne) against number supplied (No) with a non-linear least squares regression (nls). I am using a modification of Holling's (1959) disc equation to account for non-replacement of prey; Ne=No{1-exp[a(bNe-T)]} where