R: Class "DExp"

DExp-class {distr} | R Documentation

## Class "DExp"

### Description

The double exponential or Laplace distribution with rate λ has density

f(x) = 1/2 lambda e^(- lambda |x|)

C.f. `Exp-class`, `rexp`

### Objects from the Class

Objects can be created by calls of the form `DExp(rate)`. This object is a double exponential (or Laplace) distribution.

### Slots

`img`

  Object of class `"Reals"`: The space of the image of this distribution has got dimension 1 and the name "Real Space".

`param`

  Object of class `"ExpParameter"`: the parameter of this distribution (rate), declared at its instantiation

`r`

  Object of class `"function"`: generates random numbers (calls function rexp)

`d`

  Object of class `"function"`: density function (calls function dexp)

`p`

  Object of class `"function"`: cumulative function (calls function pexp)

`q`

  Object of class `"function"`: inverse of the cumulative function (calls function qexp)

`.withArith`

  logical: used internally to issue warnings as to interpretation of arithmetics

`.withSim`

  logical: used internally to issue warnings as to accuracy

`.logExact`

  logical: used internally to flag the case where there are explicit formulae for the log version of density, cdf, and quantile function

`.lowerExact`

  logical: used internally to flag the case where there are explicit formulae for the lower tail version of cdf and quantile function

`Symmetry`

  object of class `"DistributionSymmetry"`; used internally to avoid unnecessary calculations.

### Extends

Class `"AbscontDistribution"`, directly.
Class `"UnivariateDistribution"`, by class `"AbscontDistribution"`. Class `"Distribution"`, by class `"AbscontDistribution"`.

### Methods

initialize

  `signature(.Object = "DExp")`: initialize method

rate

  `signature(object = "DExp")`: returns the slot rate of the parameter of the distribution

rate<-

  `signature(object = "DExp")`: modifies the slot rate of the parameter of the distribution

*

  `signature(e1 = "DExp", e2 = "numeric")`: For the Laplace distribution we use its closedness under scaling transformations.

### Author(s)

Peter Ruckdeschel peter.ruckdeschel@uni-oldenburg.de

### See Also

`Exp-class` `ExpParameter-class` `AbscontDistribution-class` `Reals-class` `rexp`

### Examples

    D <- DExp(rate = 1) # D is a Laplace distribution with rate = 1.
    r(D)(1) # one random number generated from this distribution, e.g. 0.4190765
    d(D)(1) # Density of this distribution is 0.1839397 for x = 1.
    p(D)(1) # Probability that x < 1 is 0.8160603.
    q(D)(.1) # Probability that x < -1.609438 is 0.1.
    ## in RStudio or Jupyter IRKernel, use q.l(.)(.) instead of q(.)(.)
    rate(D) # rate of this distribution is 1.
    rate(D) <- 2 # rate of this distribution is now 2.
    3*D ###  still a DExp -distribution

[Package distr version 2.8.0 Index]