| xexp {LambertW} | R Documentation |
The Lambert W function W(z) is the inverse of u \exp(u) = z.
In versions < 0.6.0 of the package this function was denoted as H.
It is now replaced with the more descriptive xexp (and H
is deprecated).
xexp(x) deriv_xexp(x, degree = 1)
x |
a numeric vector of real/complex values. |
degree |
non-negative integer; degree of the derivative |
The n-th derviative of x \cdot \exp(x) is available in closed for as
\exp(x) \cdot (x + n).
Returns z = x \exp(x) for x \in C. If x is a vector/matrix, so is z.
plot(xexp, -5, 0.5, type="l", xlab="u", ylab="z") grid() abline(h=0, lty = 2) abline(v=0, lty = 2)