Message-ID: <338E5ABA-9EDE-41C7-A14F-4A92DFDDED0D@gmail.com>
Date: 2007-12-17T06:39:24Z
From: Charilaos Skiadas
Subject: can R solve these paired equations
In-Reply-To: <BAY141-DAV8BDEFDAA6D93C575226E3F0620@phx.gbl>
Turn your problem into an optimization one and use the various
optimization abilities of R, for instance have a look at nlm:
?nlm
As an example to solve the rather simple:
x-y=0
x+y=2
We could do:
f <- function(vals) {
x <- vals[1]
y <- vals[2]
sum(c(x-y,x+y-2)^2)
}
nlm(f, c(2,2))
PS: A google search for "rhelp solving nonlinear system of equations"
would likely have given you some starting points.
PS2: Perhaps someone more expert could comment on the differences
between optim, nlm and nlminb.
Haris Skiadas
Department of Mathematics and Computer Science
Hanover College
On Dec 17, 2007, at 12:43 AM, Xin wrote:
> Dear:
>
>
>
> I have a paired equation below. Can I solve (x,y) using R.
>
>
>
> Thanks!
>
>
>
> Xin
>
>
>
> A=327.727
>
> B=9517.336
>
> p=0.114^10
>
>
>
> (1-p)*y*(1-x)/x/(1-x^y)=A
>
> A(1+(1-x)*(1+y)/x-A))=B