# Observation/prediction matrices for rSPDE models with integer smoothness.

Source:`R/inla_rspde.R`

`spde.make.A.Rd`

Constructs observation/prediction weight matrices
for rSPDE models with integer smoothness based on `inla.mesh`

or
`inla.mesh.1d`

objects.

## Usage

```
spde.make.A(
mesh = NULL,
loc = NULL,
A = NULL,
index = NULL,
group = NULL,
repl = 1L,
n.group = NULL,
n.repl = NULL
)
```

## Arguments

- mesh
An

`inla.mesh`

, an`inla.mesh.1d`

object or a`metric_graph`

object.- loc
Locations, needed if an INLA mesh is provided

- A
The A matrix from the standard SPDE approach, such as the matrix returned by

`inla.spde.make.A`

. Should only be provided if`mesh`

is not provided.- index
For each observation/prediction value, an index into loc. Default is seq_len(nrow(A.loc)).

- group
For each observation/prediction value, an index into the group model.

- repl
For each observation/prediction value, the replicate index.

- n.group
The size of the group model.

- n.repl
The total number of replicates.

## Examples

```
# \donttest{
# devel version
if (requireNamespace("fmesher", quietly = TRUE)) {
library(fmesher)
set.seed(123)
loc <- matrix(runif(100 * 2) * 100, 100, 2)
mesh <- fm_mesh_2d(
loc = loc,
cutoff = 50,
max.edge = c(50, 500)
)
A <- spde.make.A(mesh, loc = loc)
}
# devel.tag
# }
```