Exponential {base} | R Documentation |
Density, distribution function, quantile function and random
generation for the exponential distribution with rate rate
(i.e., mean 1/rate
).
dexp(x, rate = 1, log = FALSE) pexp(q, rate = 1, lower.tail = TRUE, log.p = FALSE) qexp(p, rate = 1, lower.tail = TRUE, log.p = FALSE) rexp(n, rate = 1)
x, q |
vector of quantiles. |
p |
vector of probabilities. |
n |
number of observations to generate. |
rate |
vector of rates. |
log, log.p |
logical; if TRUE, probabilities p are given as log(p). |
lower.tail |
logical; if TRUE (default), probabilities are P[X <= x], otherwise, P[X > x]. |
If rate
is not specified, it assumes the default value of
1
.
The exponential distribution with rate λ has density
f(x) = lambda e^(- lambda x)
for x >= 0.
dexp
gives the density,
pexp
gives the distribution function,
qexp
gives the quantile function, and
rexp
generates random deviates.
exp
for the exponential function,
dgamma
for the gamma distribution and
dweibull
for the Weibull distribution, both of which
generalize the exponential.
dexp(1) - exp(-1) #-> 0 r <- rexp(100) all(abs(1 - dexp(1, r) / (r*exp(-r))) < 1e-14)