This function computes mass and stiffness matrices for a FEM approximation on R, assuming Neumann boundary conditions. These matrices are needed when discretizing the operators in rational approximations.

## Value

The function returns a list with the following elements

- G
The stiffness matrix.

- C
The mass matrix.

## Author

David Bolin davidbolin@gmail.com

## Examples

```
# create mass and stiffness matrices for a FEM discretization on [0,1]
x <- seq(from = 0, to = 1, length.out = 101)
fem <- rSPDE.fem1d(x)
```