Sorry, my answer is a bit confused. I try to explain. look this code:
curve(115.251 - 118.69 * exp(-0.123517*x),from=0,to=100) lines(c(75,75),y=c(-10,115.251),col="red") lines(c(-10,75),y=c(115.251,115.251),col="red") lines(c(20,20),y=c(-10,105),col="blue") lines(c(-10,20),y=c(105,105),col="blue")
All values of this points are fictition, only curve values are real and the y assyntotic value. in red is the y assyntotic and your minimal x, the first value of x that y is assyntotic value. The y assyntotic is easy, it is the first parameter = 115.251. To calculate the value of minimal x, I can make a program that increment x, and when y value is repeated, I know what is the minimal x. Exist another mean to make this? The another point (blue) is more difficult. I try to explain. The curve velocity is very huge before this blue point than after this point. This point is something like the inflection point in a X^2 function. Biologically this point maybe very important. I try to calculate this with the firt derivate, but I cant resolve this. Exist another solution for this? Thanks for all Inte Ronaldo Em Qua 30 Abr 2003 16:57, Douglas Bates escreveu:
I think you need to refine your questions. To me, the answers to the questions that you asked are: "x = Inf (by definition)" and "there isn't an inflection point". I don't think those are what you had in mind. "Ronaldo Reis Jr." <chrysopa at insecta.ufv.br> writes:
Hi, I have this non-linear function: y=115.251 - 118.69 * exp(-0.123517*x) I try to discovery the x value for the assyntoptic value of y and the x value where the behavior of curve change, the inflection point. How to make this? Is poss?ble to make this on R? Thanks Ronaldo
A necessidade nunca fez bons neg?cios.
-- Benjamin Franklin
--
| // | \\ [*****************************][*******************]
|| ( ? ? ) [Ronaldo Reis J?nior ][PentiumIII-600 ]
| V [UFV/DBA-Entomologia ][HD: 30 + 10 Gb ]
|| / \ [36571-000 Vi?osa - MG ][RAM: 128 Mb ]
| /(.''`.)\ [Fone: 31-3899-2532 ][Video: SiS620-8Mb ]
||/(: :' :)\ [chrysopa at insecta.ufv.br ][Modem: Pctel-onboar]
|/ (`. `'` ) \[ICQ#: 5692561 ][Kernel: 2.4.18 ]
|| ( `- ) [*****************************][*******************]
||| _/ \_Powered by GNU/Debian W/Sarge D+ || Lxuser#: 205366