If number_of_repeats is larger than 0 the calculation repeats from the control_index. The value of number_of_repeats is decreased with 1.
A first application is to do many time steps, but print only once in a while:
control_timestep 10 1. 100. ...
control_print 20 -node_dof ...
control_repeat 30 80 10
In the latter example, first 100 timesteps are taken, then results for node_dof are printed; this is repeated 80 times.
Also, this control_repeat can typically be used to perform a number of refinements combined with time stepping to a new, refined, solution. This is done a fixed number of times.
See also control_repeat_until_item.