Density, distribution function, and random generation
for the exponentially modified Gaussian distribution with
mean `mu`

and standard deviation `sigma`

of the gaussian
component, as well as scale `beta`

of the exponential
component.

```
dexgaussian(x, mu, sigma, beta, log = FALSE)
pexgaussian(q, mu, sigma, beta, lower.tail = TRUE, log.p = FALSE)
rexgaussian(n, mu, sigma, beta)
```

- x, q
Vector of quantiles.

- mu
Vector of means of the combined distribution.

- sigma
Vector of standard deviations of the gaussian component.

- beta
Vector of scales of the exponential component.

- log
Logical; If

`TRUE`

, values are returned on the log scale.- lower.tail
Logical; If

`TRUE`

(default), return P(X <= x). Else, return P(X > x) .- log.p
Logical; If

`TRUE`

, values are returned on the log scale.- n
Number of draws to sample from the distribution.

See `vignette("brms_families")`

for details
on the parameterization.