[R] to R Core T: mle function in 32bits not respecting the constrain

[Berry, Charles]

> On May 27, 2018, at 10:31 PM, francesc badia roca <fbr600 using gmail.com> wrote:
> 
> I have an issue using mle in versions of 32 bits.
> 
> I am writing a package which I want to submit to the CRAN.
> When doing the check, there is an example that has an error running in the
> 32 bits version.
> 
> The problem comes from the mle function, using it with a lower constrain.
> In 64 bits version it works fine but when I put it in the R 32 bits it
> fails. (same numbers, all equal!)
> 
> The call is:
> *mle(minuslogl = p.est,start = beta,method =
> "L-BFGS-B",lower=llim*reduction)*
> lower  = -0.01570427
> 
> The optimizer (optim function in 32 bits) display:
> -0.015704 -loglik 48.690236
> -0.015704 -loglik 48.690236
> -0.017704 -loglik 1.#QNAN0
> 
> And it is not respecting the lower constrain.
> 
> Could anyone explain me why this?

FAQ 7.31 is a likely suspect.

You might need a `safe' lower bound. Perhaps, adding a small positive constant to it will fix it.

HTH,

Chuck