[R] question about optim

[Mikyoung Jun]

Hello,

When we use optim and run into errors, such as generates NA/NaN/Inf, and 
the routine stops because of this error, is there a way to print the 
values of the argument of the functions where the error occurs? 
For example, I am doing minimizing negative log likelihood and when the 
optim stops because of those errors, I'd like to know what was the 
parameter values at that time. I heard nlm has something called 
"print.level" and I am wondering there is a way for optim as well. Thank 
you.

Mikyoung Jun