# copy (1d, 2d, 3d)¶

Copies the data on the inside edge of the domain into the ghost cells for the given boundaries. When multiple halo cells are present the data from the first halo is copied to the second, the second to the 3rd etc...

## Example¶

<Updater bcLeft>
kind = copy2d
onGrid = domain
out = [q]
entity = ghost
</Updater>