[R] Set the grid.layout programmatically?

[Felipe Carrillo]

Hello all:
Does anyone know if the grid layout function can be
set dynamically? For example if I have a column that
will be changing as new data is added monthly I would
like grid to detect the new data and create another
row or column for the new plot on the same window
instead of adding the new layout manually. The code
below shows a grid.layout of hardcoded two rows and
two columns.Thanks

pushViewport(viewport(layout=grid.layout(2,2))) 

Felipe D. Carrillo
  Fishery Biologist
  US Fish & Wildlife Service
  California, USA