[R] Relatively Simple Maximization Using Optim Doesnt Optimize

Abby Spurdle @purd|e@@ @end|ng |rom gm@||@com
Fri Mar 13 04:52:48 CET 2020

> L= 1006.536
> L= 1006.537
> L= 1006.535
> It appears to have chosen step size 0.001, not 0.00001.  It should be
> getting adequate accuracy in both 1st and 2nd derivatives.
> Those little ripples you see in the plot are not relevant.

I'm impressed.
But you're still wrong.

Try this:
#not good R code!
v = numeric ()

production3 <- function(L){
    #store in vector
    v <<- c (v, L)


optim.sol <- optim (1001, production3 ,method="CG", control = list(fnscale=-1) )

n = length (v)
print (n)

plot (1:n ,v, type="l")

After 401 iterations (on my computer), the algorithm hasn't converged.
And I note it's converging extremely slowly, so I don't see any
argument for increasing the number of iterations.

And try this:
(The first 30 steps).
plot (1:30 ,v [1:30], type="l")

Little ripples aren't going anywhere...

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