zeta {sn} | R Documentation |
The function log(2 P(x))
and its derivatives up to order 4,
if P(x) denotes the standard normal distribution function.
zeta(k, x)
k |
an integer scalar. |
x |
a vector. Missing values (NA s) are allowed, but Inf s are not.
|
k
denotes the order of the derivative. If k
is 0, the function
is evaluated, using pnorm(x)
for x>-35
, an asymptotic expansion
otherwise. For k
between 1 and 4, the derivative of that order is
evaluated. For k>4
, a warning message is issued, and a vector of
NA
s is returned.
This function is used by sn.dev
and msn.dev
, among others.
a vector; this is the k
-th order derivative evaluated at x
y <- zeta(2,seq(-20,20,by=0.5)) for(i in 0:4) curve(zeta(i,x),-3, 4, ylim = c(-1,2), col = i+1, add = i > 0)