On 19/09/2008, at 2:33 PM, sandsky wrote:
I have an error for a simple optimization problem.
It is not a simple optimization problem. It is a
totally silly optimization problem.
Is there anyone knowing
about this error?
lambda1=-9
lambda2=-6
L<-function(a){
s2i2f<-(exp(-lambda1*(250^a)-lambda2*(275^a-250^a))
-exp(-lambda1*(250^a)-lambda2*(300^a-250^a)))
logl<-log(s2i2f)
return(-logl)}
optim(1,L)
Error in optim(1, L) : function cannot be evaluated at initial
parameters
What is your difficulty? The error means what it says. Nothing
more, nothing less.
Did you ***try*** just typing ``L(1)'' to see what you get?
Hint: exp(2250) is infinity as far as your --- or anyone else's ---
computer
is concerned.
cheers,
Rolf Turner
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