# Simulation of a fractional SPDE using a rational SPDE approximation

Source:`R/fractional.computations.R`

`simulate.rSPDEobj.Rd`

The function samples a Gaussian random field based on a pre-computed rational SPDE approximation.

## Usage

```
# S3 method for rSPDEobj
simulate(object, nsim = 1, seed = NULL, ...)
```

## Arguments

- object
The rational SPDE approximation, computed using

`fractional.operators()`

,`matern.operators()`

, or`spde.matern.operators()`

.- nsim
The number of simulations.

- seed
an object specifying if and how the random number generator should be initialized (‘seeded’).

- ...
Currently not used.

## Examples

```
# Sample a Gaussian Matern process on R using a rational approximation
kappa <- 10
sigma <- 1
nu <- 0.8
range <- sqrt(8 * nu) / kappa
# create mass and stiffness matrices for a FEM discretization
x <- seq(from = 0, to = 1, length.out = 101)
fem <- rSPDE.fem1d(x)
# compute rational approximation
op <- matern.operators(
range = range, sigma = sigma,
nu = nu, loc_mesh = x, d = 1,
parameterization = "matern"
)
# Sample the model and plot the result
Y <- simulate(op)
plot(x, Y, type = "l", ylab = "u(x)", xlab = "x")
```