Add a constraint of renewable ressource - or-tools

I am new to these optimisation problems, I just found the or-tools library and saw that cp_model can fix problems that are close to mine.
I have printers and some tasks, that I want to schedule in order to finish the production the earliest. The tasks uses time on machine and raw material, that I must refill at the end of coil. For the moment, I don't consider changing a plastic coil before using all the material.
Here is some information about my situation:
1- The printers are all same, they can do every task, with the same efficiency.
2- A printer can only print one task at a time.
3- A printer cannot start without human around, so tasks can start only at certain hours (in the code below, from 0AM to 10 AM).
4- A task can finish at any time.
5- If a printer has no more material, it needs to be change, this can happen only on opening hours.
6- If a printer has no more material, the task is paused until new material is put.
7- I consider having unlimited quantity of material coil.
Thanks to examples and some search in the documentation, I have been able to fix all the issues that are not related to material. I have been able to set a maximum quantity per machine, but it is not my issue.
I don't understand how I can pause/resume my intervals (for the moment I set the duration to a fixed one).
from ortools.sat.python import cp_model
from ortools.util.python import sorted_interval_list
import random
Domain = sorted_interval_list.Domain
def main():
random.seed(0)
nb_jobs = 10
nb_machine = 2
horizon = 30000000
job_list = [] #Job : (id,time,quantity)
listOfEnds = []
quantityPerMachine = []
maxQuantity = 5
#create the jobs
for i in range(nb_jobs):
time = random.randrange(1,24)
quantity = random.randrange(1,4)
job_list.append([i,time,quantity])
print([job[1] for job in job_list])
print("total time to print = ",horizon)
print("quantity")
print([job[2] for job in job_list])
print("total quantity = ",sum([job[2] for job in job_list]))
model = cp_model.CpModel()
makespan = model.NewIntVar(0, horizon, 'makespan')
machineForJob = {}
#boolean variable for each combination of machine and job. if True then machine works on this job
for machine in range(nb_machine):
for job in job_list:
j = job[0]
machineForJob[(machine,j)]=(model.NewBoolVar(f'x[{machine},{j}]'))
#for each job, apply sum()==1 to ensure one machine works on each job only
for j in range(nb_jobs):
model.Add(sum([machineForJob[(machine,j)] for machine in range(nb_machine)])==1)
#set the affectation of the jobs
time_intervals={}
starts = {}
ends = {}
#Time domain represents working hours when someone can start the taks
timeDomain = []#[[0],[1],[2],[3],[4],[5],[6],[7],[8],[9],[10],[24],[25],[26]]
for i in range(20):
for j in range(10):
t= [j +i*24]
timeDomain.append(t)
for machine in range(nb_machine):
time_intervals[machine] = []
for job in job_list:
j = job[0]
duration = job[1]
starts[(machine,j)] = model.NewIntVarFromDomain(Domain.FromIntervals(timeDomain),f'start {machine},{j}')
ends[(machine,j)] = (model.NewIntVar(0, horizon, f'end {machine},{j}'))
time_intervals[machine].append(model.NewOptionalIntervalVar(starts[(machine,j)], duration, ends[(machine,j)],
machineForJob[(machine,j)],f'interval {machine},{j} '))
#time should not overlap, quantity of raw material is limited,
for machine in range(nb_machine):
#model.Add(quantityPerMachine[machine] <= maxQuantity) Not working as expected as the raw material cannot be refilled
model.AddNoOverlap(time_intervals[machine])
#calculate time per machine
time_per_machine = []
for machine in range(nb_machine):
q = 0
s = 0
for job in job_list:
s+= job[1]*machineForJob[(machine,job[0])]
listOfEnds.append(ends[(machine,job[0])])
q+= job[2]*machineForJob[(machine,job[0])]
time_per_machine.append(s)
quantityPerMachine.append(q)
#Goal is to finish all taks earliest
model.AddMaxEquality(makespan,listOfEnds)
model.Minimize(makespan)
solver = cp_model.CpSolver()
# Sets a time limit of 10 seconds.
solver.parameters.max_time_in_seconds = 600.0
#Solve and prints
status = solver.Solve(model)
if status == cp_model.OPTIMAL or status == cp_model.FEASIBLE:
print("optimal =",status == cp_model.OPTIMAL )
print(f'Total cost = {solver.ObjectiveValue()}')
for i in range(nb_machine):
for j in range(nb_jobs):
if solver.BooleanValue(machineForJob[(i,j)]):
print(
f'Machine {i} assigned to Job {j} Time = {job_list[j][1]},Quantity = {job_list[j][2]}')
print(f"[{solver.Value(starts[(i,j)])} ,{solver.Value(ends[(i,j)])}]")
else:
print('No solution found.')
# Statistics.
print('\nStatistics')
print(' - conflicts: %i' % solver.NumConflicts())
print(' - branches : %i' % solver.NumBranches())
print(' - wall time: %f s' % solver.WallTime())

Related

Saving synchronised 7T fMRI Triggers received via USB connected NNL SyncBox, on every TR and Task Response Keypress (PsychoPy)

I would like to get synchronised timings and number of triggers for each single pulse sent by the 7T MRI scanner together with each single SPACEBAR keypress as a participant’s response when particular letters (A, B, C, X, Y) are presented on the screen, also the stimulus start time with each corresponding trigger.
So far I have added a “Waiting for scanner” routine where I get the first pulse via USB connected NNL Synbox saved in the .csv data file but I want to save each single pulse (TR) and timings. Triggers are automatically emulated as letter ‘s’ sent by the NNL Synbox.
# Code component: Creat routine "Wait for Scanner"
text_wait = visual.TextStim(win=win, name='text_wait',
text='Waiting for scanner...',
font='Arial',
pos=(0, 0), height=0.8, wrapWidth=None, ori=0,
color='white', colorSpace='rgb', opacity=1,
languageStyle='LTR',
depth=0.0);
#Set first MR Trigger
mr_trigger_number = [] # list for triggers
mr_trigger_time = [] # list for time of each trigger
ScannerKeyboard = keyboard.Keyboard() # set keyboard
count_mr_trigger = 0 # counts amount of MR scanner trigger, starts with zero
start_trigger = ScannerKeyboard.getKeys(keyList=['s'], waitRelease = False) # experiment starts with MR Scanner "s"
# Draw waiting Screen until "s" is sent from NNL Syncbox
while len(start_trigger) == 0: # if no trigger was sent show:
text_wait.draw() # Text "Waiting for scanner"
win.flip()
start_trigger = ScannerKeyboard.getKeys(keyList=['s'], waitRelease = False) # show text_wait until one "s" was received
# Get timing information and store trigger number
onset = core.getTime() # get Onset time of trigger
count_mr_trigger = count_mr_trigger + 1 # count MR Scanner trigger, add "1!
# Save time and number of MR Trigger
thisExp.addData('MR_trigger_time',onset) # save trigger time of onset
thisExp.addData('MR_trigger_number',count_mr_trigger)
And also I used the following code component in > Each Frame tab of 2 trials conditions to save the stimuli onset timings when a pulse 's' is received. This works fine but stimulus start time > stimulus_start_time = globalClock.getTime() - mr_trigger_time is saved based on first pulse only as I am unable to save each pulse timings.
#save stimulus onset time for two types of trial conditions
if trials.thisN == 0 and frameN == 0:
loop_start_time = globalClock.getTime() - mr_trigger_time
elif frameN == 1:
stimulus_start_time = globalClock.getTime() - mr_trigger_time
# store the data:
thisExp.addData('stimulus_start_time', stimulus_start_time)
if trials_2.thisN == 0 and frameN == 0:
loop_start_time = globalClock.getTime() - mr_trigger_time
elif frameN == 1:
stimulus_start_time = globalClock.getTime() - mr_trigger_time
# store the data:
thisExp.addData('stimulus_start_time', stimulus_start_time)
However, I want to record and save timings of each trigger pulse when a SPACEBAR response is pressed on a target letter (stimulus) by a participant, to compare the timings with accuracy and reaction times of the task with each corresponding trigger timings.
I would really appreciate your valuable suggestions on how to work around this, as I am quite new to the PsychoPy. I also posted to the PsychoPy forum but haven't got any update so far.
Thanks in advance!

How to pass the number of total users to simulate and spawn rate in the locust script itself

How do I pass the number of total users to simulate and spawn rate in the Web UI when I run the locust file, instead, I would like to pass them as variables in the script itself?
class QuickstartUser(HttpUser):
wait_time = between(1, 2.5)
users = 10
spawn_rate = 1
#task
def on_start(self):
filenumber="ABC"
# Get file info
response = self.client.get(f"/files/" + filenumber)
json_var = response.json()
print("response Json: ", json_var)
time.sleep(1)
You could probably do it by accessing the Runner in code, but it would be much easier if you used a Load Shape.
class MyCustomShape(LoadTestShape):
time_limit = 600
spawn_rate = 20
def tick(self):
run_time = self.get_run_time()
if run_time < self.time_limit:
# User count rounded to nearest hundred.
user_count = round(run_time, -2)
return (user_count, spawn_rate)
return None
tick is called automatically, you just have to return a tuple of the user count and spawn rate you want. You can do whatever work you want to calculate what the users and rate should be. There are more examples in the GitHub repo.

Storage values using os.stat(filename)

I'm trying to create an EDUCATIONAL PURPOSES ONLY virus. I do not plan on spreading it. It's purpose is to grow a file to the point your storage is full and slow your computer down. It prints the size of the file every 0.001 seconds. With that, I also want to know how fast it is growing the file. The following code doesn't seem to let it run:
class Vstatus():
def _init_(Status):
Status.countspeed == True
Status.active == True
Status.growingspeed == 0
import time
import os
#Your storage is at risk of over-expansion. Please do not let this file run forever, as your storage will fill continuously.
#This is for educational purposes only.
while Vstatus.Status.countspeed == True:
f = open('file.txt', 'a')
f.write('W')
fsize = os.stat('file.txt')
Key1 = fsize
time.sleep(1)
Key2 = fsize
Vstatus.Status.growingspeed = (Key2 - Key1)
Vstatus.Status.countspeed = False
while Vstatus.Status.active == True:
time.sleep(0.001)
f = open('file.txt', 'a')
f.write('W')
fsize = os.stat('file.txt')
print('size:' + fsize.st_size.__str__() + ' at a speed of ' + Vstatus.Status.growingspeed + 'bytes per second.')
This is for Educational Purposes ONLY
The main error I keep getting when running the file is here:
TypeError: unsupported operand type(s) for -: 'os.stat_result' and 'os.stat_result'
What does this mean? I thought os.stat returned an integer Can I get a fix on this?
Vstatus.Status.growingspeed = (Key2 - Key1)
You can't subtract os.stat objects. Your code also has some other problems. Your loops will run sequentially, meaning that your first loop will try to estimate how quickly the file is being written to without writing anything to the file.
import time # Imports at the top
import os
class VStatus:
def __init__(self): # double underscores around __init__
self.countspeed = True # Assignment, not equality test
self.active = True
self.growingspeed = 0
status = VStatus() # Make a VStatus instance
# You need to do the speed estimation and file appending in the same loop
with open('file.txt', 'a+') as f: # Only open the file once
start = time.time() # Get the current time
starting_size = os.fstat(f.fileno()).st_size
while status.active: # Access the attribute of the VStatus instance
size = os.fstat(f.fileno()).st_size # Send file desciptor to stat
f.write('W') # Writing more than one character at a time will be your biggest speed up
f.flush() # make sure the byte is written
if status.countspeed:
diff = time.time() - start
if diff >= 1: # More than a second has gone by
status.countspeed = False
status.growingspeed = (os.fstat(f.fileno()).st_size - starting_size)/diff # get rate of growth
else:
print(f"size: {size} at a speed of {status.growingspeed}")

Simpy: How can I represent failures in a train subway simulation?

New python user here and first post on this great website. I haven't been able to find an answer to my question so hopefully it is unique.
Using simpy I am trying to create a train subway/metro simulation with failures and repairs periodically built into the system. These failures happen to the train but also to signals on sections of track and on plaforms. I have read and applied the official Machine Shop example (which you can see resemblance of in the attached code) and have thus managed to model random failures and repairs to the train by interrupting its 'journey time'.
However I have not figured out how to model failures of signals on the routes which the trains follow. I am currently just specifying a time for a trip from A to B, which does get interrupted but only due to train failure.
Is it possible to define each trip as its own process i.e. a separate process for sections A_to_B and B_to_C, and separate platforms as pA, pB and pC. Each one with a single resource (to allow only one train on it at a time) and to incorporate random failures and repairs for these section and platform processes? I would also need to perhaps have several sections between two platforms, any of which could experience a failure.
Any help would be greatly appreciated.
Here's my code so far:
import random
import simpy
import numpy
RANDOM_SEED = 1234
T_MEAN_A = 240.0 # mean journey time
T_MEAN_EXPO_A = 1/T_MEAN_A # for exponential distribution
T_MEAN_B = 240.0 # mean journey time
T_MEAN_EXPO_B = 1/T_MEAN_B # for exponential distribution
DWELL_TIME = 30.0 # amount of time train sits at platform for passengers
DWELL_TIME_EXPO = 1/DWELL_TIME
MTTF = 3600.0 # mean time to failure (seconds)
TTF_MEAN = 1/MTTF # for exponential distribution
REPAIR_TIME = 240.0
REPAIR_TIME_EXPO = 1/REPAIR_TIME
NUM_TRAINS = 1
SIM_TIME_DAYS = 100
SIM_TIME = 3600 * 18 * SIM_TIME_DAYS
SIM_TIME_HOURS = SIM_TIME/3600
# Defining the times for processes
def A_B(): # returns processing time for journey A to B
return random.expovariate(T_MEAN_EXPO_A) + random.expovariate(DWELL_TIME_EXPO)
def B_C(): # returns processing time for journey B to C
return random.expovariate(T_MEAN_EXPO_B) + random.expovariate(DWELL_TIME_EXPO)
def time_to_failure(): # returns time until next failure
return random.expovariate(TTF_MEAN)
# Defining the train
class Train(object):
def __init__(self, env, name, repair):
self.env = env
self.name = name
self.trips_complete = 0
self.broken = False
# Start "travelling" and "break_train" processes for the train
self.process = env.process(self.running(repair))
env.process(self.break_train())
def running(self, repair):
while True:
# start trip A_B
done_in = A_B()
while done_in:
try:
# going on the trip
start = self.env.now
yield self.env.timeout(done_in)
done_in = 0 # Set to 0 to exit while loop
except simpy.Interrupt:
self.broken = True
done_in -= self.env.now - start # How much time left?
with repair.request(priority = 1) as req:
yield req
yield self.env.timeout(random.expovariate(REPAIR_TIME_EXPO))
self.broken = False
# Trip is finished
self.trips_complete += 1
# start trip B_C
done_in = B_C()
while done_in:
try:
# going on the trip
start = self.env.now
yield self.env.timeout(done_in)
done_in = 0 # Set to 0 to exit while loop
except simpy.Interrupt:
self.broken = True
done_in -= self.env.now - start # How much time left?
with repair.request(priority = 1) as req:
yield req
yield self.env.timeout(random.expovariate(REPAIR_TIME_EXPO))
self.broken = False
# Trip is finished
self.trips_complete += 1
# Defining the failure
def break_train(self):
while True:
yield self.env.timeout(time_to_failure())
if not self.broken:
# Only break the train if it is currently working
self.process.interrupt()
# Setup and start the simulation
print('Train trip simulator')
random.seed(RANDOM_SEED) # Helps with reproduction
# Create an environment and start setup process
env = simpy.Environment()
repair = simpy.PreemptiveResource(env, capacity = 1)
trains = [Train(env, 'Train %d' % i, repair)
for i in range(NUM_TRAINS)]
# Execute
env.run(until = SIM_TIME)
# Analysis
trips = []
print('Train trips after %s hours of simulation' % SIM_TIME_HOURS)
for train in trains:
print('%s completed %d trips.' % (train.name, train.trips_complete))
trips.append(train.trips_complete)
mean_trips = numpy.mean(trips)
std_trips = numpy.std(trips)
print "mean trips: %d" % mean_trips
print "standard deviation trips: %d" % std_trips
it looks like you are using Python 2, which is a bit unfortunate, because
Python 3.3 and above give you some more flexibility with Python generators. But
your problem should be solveable in Python 2 nonetheless.
you can use sub processes within in a process:
def sub(env):
print('I am a sub process')
yield env.timeout(1)
# return 23 # Only works in py3.3 and above
env.exit(23) # Workaround for older python versions
def main(env):
print('I am the main process')
retval = yield env.process(sub(env))
print('Sub returned', retval)
As you can see, you can use Process instances returned by Environment.process()
like normal events. You can even use return values in your sub proceses.
If you use Python 3.3 or newer, you don’t have to explicitly start a new
sub-process but can use sub() as a sub routine instead and just forward the
events it yields:
def sub(env):
print('I am a sub routine')
yield env.timeout(1)
return 23
def main(env):
print('I am the main process')
retval = yield from sub(env)
print('Sub returned', retval)
You may also be able to model signals as resources that may either be used
by failure process or by a train. If the failure process requests the signal
at first, the train has to wait in front of the signal until the failure
process releases the signal resource. If the train is aleady passing the
signal (and thus has the resource), the signal cannot break. I don’t think
that’s a problem be cause the train can’t stop anyway. If it should be
a problem, just use a PreemptiveResource.
I hope this helps. Please feel welcome to join our mailing list for more
discussions.

Simpy subway simulation: how to fix interrupt failure of class train while queueing for a resource?

I am working on a train simulation in simpy and have had success so far with a single train entity following the code below.
The trains processes are sections followed by platforms. Each section and platform has a resource of 1 to ensure that only one train utilises at a time.
However I can't find a way to get around the error below:
When I add in a second train to the simulation there is occasionally the situation where one train waits for an unavailable resource and then a failure occurs on that train while it is waiting.
I end up with an Interrupt: Interrupt() error.
Is there a way around these failing queues for resources?
Any help is much appreciated.
import random
import simpy
import numpy
# Configure parameters for the model
RANDOM_SEED = random.seed() # makes results repeatable
T_MEAN_SECTION = 200.0 # journey time (seconds)
DWELL_TIME = 30.0 # dwell time mean (seconds)
DWELL_TIME_EXPO = 1/DWELL_TIME # for exponential distribution
MTTF = 600.0 # mean time to failure (seconds)
TTF_MEAN = 1/MTTF # for exponential distribution
REPAIR_TIME = 120.0 # mean repair time for when failure occurs (seconds)
REPAIR_TIME_EXPO = 1/REPAIR_TIME # for exponential distribution
NUM_TRAINS = 2 # number of trains to simulate
SIM_TIME_HOURS = 1 # sim time in hours
SIM_TIME_DAYS = SIM_TIME_HOURS/18.0 # number of days to simulate
SIM_TIME = 3600 * 18 * SIM_TIME_DAYS # sim time in seconds (this is used in the code below)
# Defining the times for processes
def Section(): # returns processing time for platform 7 Waterloo to 26 Bank
return T_MEAN_SECTION
def Dwell(): # returns processing time for platform 25 Bank to platform 7 Waterloo
return random.expovariate(DWELL_TIME_EXPO)
def time_to_failure(): # returns time until next failure
return random.expovariate(TTF_MEAN)
# Defining the train
class Train(object):
def __init__(self, env, name, repair):
self.env = env
self.name = name
self.trips_complete = 0
self.num_saf = 0
self.sum_saf = 0
self.broken = False
# Start "running" and "downtime_train" processes for the train
self.process = env.process(self.running(repair))
env.process(self.downtime_train())
def running(self, repair):
while True:
# request section A
request_SA = sectionA.request()
########## SIM ERROR IF FAILURE OCCURS HERE ###########
yield request_SA
done_in_SA = Section()
while done_in_SA:
try:
# going on the trip
start = self.env.now
print('%s leaving platform at time %d') % (self.name, env.now)
# processing time
yield self.env.timeout(done_in_SA)
# releasing the section resource
sectionA.release(request_SA)
done_in_SA = 0 # Set to 0 to exit while loop
except simpy.Interrupt:
self.broken = True
delay = random.expovariate(REPAIR_TIME_EXPO)
print('Oh no! Something has caused a delay of %d seconds to %s at time %d') % (delay, self.name, env.now)
done_in_SA -= self.env.now - start # How much time left?
with repair.request(priority = 1) as request_D_SA:
yield request_D_SA
yield self.env.timeout(delay)
self.broken = False
print('Okay all good now, failure fixed on %s at time %d') % (self.name, env.now)
self.num_saf += 1
self.sum_saf += delay
# request platform A
request_PA = platformA.request()
########## SIM ERROR IF FAILURE OCCURS HERE ###########
yield request_PA
done_in_PA = Dwell()
while done_in_PA:
try:
# platform process
start = self.env.now
print('%s arriving to platform A and opening doors at time %d') % (self.name, env.now)
yield self.env.timeout(done_in_PA)
print('%s closing doors, ready to depart platform A at %d\n') % (self.name, env.now)
# releasing the platform resource
platformA.release(request_PA)
done_in_PA = 0 # Set to 0 to exit while loop
except simpy.Interrupt:
self.broken = True
delay = random.expovariate(REPAIR_TIME_EXPO)
print('Oh no! Something has caused a delay of %d seconds to %s at time %d') % (delay, self.name, env.now)
done_in_PA -= self.env.now - start # How much time left?
with repair.request(priority = 1) as request_D_PA:
yield request_D_PA
yield self.env.timeout(delay)
self.broken = False
print('Okay all good now, failure fixed on %s at time %d') % (self.name, env.now)
self.num_saf += 1
self.sum_saf += delay
# Round trip is finished
self.trips_complete += 1
# Defining the failure event
def downtime_train(self):
while True:
yield self.env.timeout(time_to_failure())
if not self.broken:
# Only break the train if it is currently working
self.process.interrupt()
# Setup and start the simulation
print('Train trip simulator')
random.seed(RANDOM_SEED) # Helps with reproduction
# Create an environment and start setup process
env = simpy.Environment()
# Defining resources
platformA = simpy.Resource(env, capacity = 1)
sectionA = simpy.Resource(env, capacity = 1)
repair = simpy.PreemptiveResource(env, capacity = 10)
trains = [Train(env, 'Train %d' % i, repair)
for i in range(NUM_TRAINS)]
# Execute
env.run(until = SIM_TIME)
Your processes request a resource and never release it. That’s why the second trains waits forever for its request to succeed. While it is waiting, the failure process seems to interrupt the process. That’s why you get an error. Please read the guide to resources to understand how SimPy’s resources work and, especially, how to release a resource when you are done.