Run iterateM_ a specific number of times (Haskell)(Repa)

Question

I have a simulation where the result of each step is the input for the next step. The simulation itself uses the IO Monad (Repa:ComputeP) and I would like to write the result of each step to a file as it is running.

The closest I can think of using is the iterateM_ action on my simulation step, but this will run forever. Is there a way to only call the iterateM_ a specific number of times?

Relevant code:

main :: IO ()
main = do
  us <- iterateM_ (\u -> (computeP (simulStep u) :: IO (Array U DIM2 Double))) u0
  zipWithM_ writeMatrixToTextFile (map show [1..]) us

(Or is there a better alternative for what I would like to do)