# Exp-class

From distr v2.3.1
by Peter Ruckdeschel

##### Class "Exp"

The exponential distribution with rate $\lambda$ has density
$$f(x) = \lambda {e}^{- \lambda x}$$
for $x \ge 0$.
C.f. `rexp`

- Keywords
- distribution

##### Objects from the Class

Objects can be created by calls of the form `Exp(rate)`

.
This object is an exponential distribution.

##### Extends

Class `"ExpOrGammaOrChisq"`

, directly.
Class `"AbscontDistribution"`

, by class `"ExpOrGammaOrChisq"`

.
Class `"UnivariateDistribution"`

, by class `"AbscontDistribution"`

.
Class `"Distribution"`

, by class `"AbscontDistribution"`

.

##### Is-Relations

By means of `setIs`

, R ``knows'' that a distribution object `obj`

of class `"Exp"`

also is
a Gamma distribution with parameters `shape = 1, scale = 1/rate(obj)`

and a Weibull distribution with
parameters `shape = 1, scale = 1/rate(obj)`

##### concept

- Exponential distribution
- memoryless distribution
- absolutely continuous distribution
- S4 distribution class
- generating function

##### See Also

`ExpParameter-class`

`AbscontDistribution-class`

`Reals-class`

`rexp`

##### Examples

```
E <- Exp(rate = 1) # E is a exp distribution with rate = 1.
r(E)(1) # one random number generated from this distribution, e.g. 0.4190765
d(E)(1) # Density of this distribution is 0.3678794 for x = 1.
p(E)(1) # Probability that x < 1 is 0.6321206.
q(E)(.1) # Probability that x < 0.1053605 is 0.1.
rate(E) # rate of this distribution is 1.
rate(E) <- 2 # rate of this distribution is now 2.
is(E, "Gammad") # yes
as(E,"Gammad")
is(E, "Weibull")
E+E+E ### a Gammad -distribution
2*E+Gammad(scale=1)
```

*Documentation reproduced from package distr, version 2.3.1, License: LGPL-3*

### Community examples

Looks like there are no examples yet.