D(expr, namevec) deriv(expr, namevec, function.arg = NULL, tag = ".expr")
expr
| expression which should be derivated |
namevec
| character vector, giving the variable names with respect to which derivatives will be computed. |
function.arg
| ... ?? ... |
tag
| ... ?? ... |
D
is modelled after its S pendant for taking simple symbolic
derivatives.
deriv
is a generic function with a default and a
formula
method. It returns a call
for computing
the expr
and its (partial) derivatives, simultaneously.
It uses so called "algorithmic derivatives".
Currently, deriv.formula
just calls deriv.default
after
extracting the expression to the right of ~
.
D
returns an expression and therefore can easily be iterated for
higher derivatives.
deriv
returns a call
object which becomes an
expression
when evaluated once.
Evaluation of the latter expression returns the function values with a
".gradient"
attribute containing the gradient matrix.
RHOME/src/main/deriv.c
.
It's author, MM, has only got a vague idea and thinks that a help page
is better than none....
nlm
for numeric minimization which should make use of derivatives.