Thank you. The nlsr package will be a satisfactory alternative once the bug in
fnDeriv(..., hessian=TRUE) is patched. I have notified the maintainer.
Jerry
-Original Message-
From: Duncan Murdoch [mailto:murdoch.dun...@gmail.com]
Sent: Friday, February 17, 2017 6:05 PM
To: Jerry Lewis
On 17/02/2017 1:59 PM, Jerry Lewis wrote:
The derivative table resides in the function D. In S+ that table is extensible
because it is written in the S language. R is faster but less flexible, since
that table is programmed in C. It would be useful if R provided a mechanism
for extending th
The issue is that without an extensible derivative table or the proposed
extensions, it is not possible to automatically produce (without manual
modification of the deriv3 output) a function that avoids catastrophic
cancellation regardless of the working range.
Manual modification is not onerou
Hi.
Unless I'm misremembering, log, exp, sin, cos, and tan are all handled in
deriv3. The functions listed are specially coded slightly more accurate
versions but can be substituted with native ones for which deriv/deriv3
will work automatically. I believe that if you write your functions using
The derivative table resides in the function D. In S+ that table is extensible
because it is written in the S language. R is faster but less flexible, since
that table is programmed in C. It would be useful if R provided a mechanism
for extending the derivative table, or barring that, provide
