CiwPython/Ciw

Pause and restart simulation

Closed this issue · 2 comments

Would it be possible to run the simulation up to a certain point, stop it to inspect the current status and then restart it again?

This would be equivalent to initialize the simulation with a known initial state.
Possibly related to: #98 ?

Alternatively, does the tracker have the ability to inspect the results while the simulation is running?

Thanks!

Hi @lec00q

Pausing and restarting the simulation can be done by running until a certain time, then using the same Simulation object again to run the rest of the time.

For example, running a simulatiuon for 20 time units, but pausing at 10.

First consider not pausing at all:

>>> N = ciw.create_network(
...     arrival_distributions=[ciw.dists.Exponential(1)],
...     service_distributions=[ciw.dists.Exponential(2)],
...     number_of_servers=[2]
... )

>>> ciw.seed(0)
>>> Q = ciw.Simulation(N)
>>> Q.simulate_until_max_time(20)
>>> recs = Q.get_all_records()

>>> len(recs)
14

>>> [r.arrival_date for r in recs]
[2.4063202566068163,
 1.8606071110652234,
 3.122275006373967,
 4.65381985396865,
 5.301223323521953,
 7.688417791844613,
 8.019477683822869,
 8.982778780921402,
 11.387908978434579,
 13.421061759569643,
 13.049784186726923,
 15.712096692891578,
 16.35102601912159,
 16.9204908622033]

Now lets run it for the first 10 time units, lookn at the resutls, then continue it to the end of the simulation:

>>> ciw.seed(0)
>>> Q = ciw.Simulation(N)
>>> Q.simulate_until_max_time(10)
>>> recs_pause = Q.get_all_records()

>>> len(recs_pause)
8

>>> [r.arrival_date for r in recs_pause]
[2.4063202566068163,
 1.8606071110652234,
 3.122275006373967,
 4.65381985396865,
 5.301223323521953,
 7.688417791844613,
 8.019477683822869,
 8.982778780921402]

>>> # Now continue to simulate the same object until time 20:
>>> Q.simulate_until_max_time(20)
>>> recs_afterpause = Q.get_all_records()

>>> len(recs_afterpause)
14

>>> [r.arrival_date for r in recs_afterpause]
[2.4063202566068163,
 1.8606071110652234,
 3.122275006373967,
 4.65381985396865,
 5.301223323521953,
 7.688417791844613,
 8.019477683822869,
 8.982778780921402,
 11.387908978434579,
 13.421061759569643,
 13.049784186726923,
 15.712096692891578,
 16.35102601912159,
 16.9204908622033]

Hope this helps

Hi @geraintpalmer, I was trying that but I wasn't sure about the result. My bad!

I will give it a go again after your suggestion.

Many thanks!