Reference

class DatetimeUnit(start: datetime | time = datetime.time(0, 0), unit: timedelta = datetime.timedelta(seconds=60))

The time unit of the Model class.

Parameters:

start – The start time of the scheduling problem. Defaults to time().
unit – The time unit for the scheduling problem. Defaults to timedelta(minutes=1).

Examples

>>> from amplify_sched import *
>>> dtime = DatetimeUnit(start=datetime(year=2023, month=1, day=1), unit=timedelta(seconds=60))
>>> dtime
{'start': datetime.datetime(2023, 1, 1, 0, 0), 'unit': datetime.timedelta(seconds=60)}

from_int_datetime(int_datetime: int) → datetime | timedelta

convert int to datetime using the specified time unit

Parameters:

int_datetime – int to convert to datetime

Returns:

A datetime or timedelta value representing int_datetime converted using the specified: time unit.

from_int_timedelta(int_timedelta: int) → timedelta

convert int to timedelta using the specified time unit

Parameters:: int_timedelta – int to convert to timedelta
Returns:: A timedelta value representing int_timedelta converted using the specified time unit.

property start: datetime | time: start time

to_int_datetime(dtime: datetime | time) → int

Convert datetime to int using the time unit.

to_int_datetime converts dtime to an integer value representing the time duration between dtime and the specified start time, in the specified time unit.

Parameters:: dtime – datetime object
Returns:: the time duration

to_int_timedelta(delta: timedelta) → int

convert timedelta to int using the specified time unit

Parameters:: dtime – timedelta to convert to int
Returns:: An integer value representing the timedelta in the specified time unit

property unit: timedelta: time unit

DependentJob contains the properties of dependency

Parameters:

parent – parent object which this object belong to
job – dependent job to append
interval_time – interval time or times (lower and upper bounds)

class DependentJobs(parent: Job)

DependentJobs is container of dependent job.

DependentJobs is managed as list of Job.

Parameters:: parent – parent object which this object belong to

append dependent job

Parameters:: value – job or tuple of job and interval_time (either a time or times to specify lower and upper bounds.)

class Job(name: str = '')

A class managing a Job.

In a scheduling problem, a Job is a collection of multiple tasks. A job is completed by processing each task in turn.

Parameters:: name – job name. Defaults to “”

add dependent jobs

Parameters:

job – depandent job
interval_time – interval time

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs.add("Job B")
>>> model.jobs.add("Job C")
>>> model.jobs["Job A"].add_dependent_jobs("Job B")
>>> model.jobs["Job A"].add_dependent_jobs("Job C", (5, 10))
>>> model.jobs["Job A"].dependent_jobs
[{'job_id': 1, 'interval_time_lower_bound': None, 'interval_time_upper_bound': None}, {'job_id': 2, 'interval_time_lower_bound': 5, 'interval_time_upper_bound': 10}]

append(task: Task | None = None) → None

append task

Parameters:: task – task for appending. Defaults to None.
Raises:: ValueError – If task is already registerd

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0]  
{'index': 0, 'processing_times': {}, 'required_resources': None, 'required_buffer_size': None,
 'transportation_times': None, 'release_time': None, 'deadline': None}

property dependent_jobs: DependentJobs

dependent jobs for this job

Dependent jobs is managed as list. During registration, the existence of the job in the model is checked. Registering a machine name that does not exist in the model will result in a ValueError.

Parameters:: job – depandent job

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs.add("Job B")
>>> model.jobs["Job A"].dependent_jobs.append("Job B")
>>> model.jobs["Job A"].dependent_jobs
[{'job_id': 1, 'interval_time_lower_bound': None, 'interval_time_upper_bound': None}]

property index: int

job index

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].index
0
>>> model.jobs.add("Job B")
>>> model.jobs["Job B"].index
1

property name: str

job name

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].name
'Job A'

property no_wait: bool | None

no wait flag

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].no_wait = True
>>> model.jobs["Job A"].no_wait
True

property num_process: int

number of processes

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].num_process
0
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"].num_process
1

task(process: int) → Task

returns a task for the given process

Parameters:: process – task index
Returns:: a task for the given process

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"].task(0)  
{'index': 0, 'processing_times': {}, 'required_resources': None, 'required_buffer_size': None,
 'transportation_times': None, 'release_time': None, 'deadline': None}

class Jobs(parent: Model)

Jobs is container of Job.

Jobs is managed as dict. Key is job name and value is Job.

Parameters:: parent – parent object which this object belong to

add(job: str | Job) → None

add job

Parameters:: job – job to adding
Raises:: ValueError – If job has no name

copy() → dict[str, Job]

get(key: str, default: Any | None = None) → Job

items()

keys()

values()

class Machine(name: str = '')

A class managing a machine

In a scheduling problem, a machine processes tasks in a specified time range.

Parameters:: name – machine name. Defaults to “”

add_maintenance_time(start: datetime | time | int, end: datetime | time | int) → None

add maintenance time

Parameters:

start – maintenance start time
end – maintenance end time

Examples

>>> model = Model()
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].add_maintenance_time(10, 15)
>>> model.machines["Machine A"].maintenance_times
[(10, 15)]

add setup time

Add setup_time (time taken to switch from previous task to next task).

Parameters:

setup_time – setup time
prev_task – previous task
next_task – next task

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs.add("Job B")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job B"].append(Task())
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].add_setup_time(10, "Job A", "Job B")
>>> model.machines["Machine A"].setup_times
[(10, ['Job A'], ['Job B'])]

property buffer_size: int | None

machine buffer size

Examples

>>> model = Model()
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].buffer_size = 10
>>> model.machines["Machine A"].buffer_size
10

property index: int

machine index

Examples

>>> model = Model()
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].index
0
>>> model.machines.add("Machine B")
>>> model.machines["Machine B"].index
1

property maintenance_times: List[TimeRange]

machine maintenance times

Examples

>>> model = Model()
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].maintenance_times.append((10, 15))
>>> model.machines["Machine A"].maintenance_times
[(10, 15)]

property name: str

machine name

Examples

>>> model = Model()
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].name
'Machine A'

property setup_times: SetupTimes

machine setup times

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs.add("Job B")
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].setup_times.append((10, "Job A", "Job B"))
>>> model.machines["Machine A"].setup_times
[(10, ['Job A'], ['Job B'])]

class Machines(parent: Model)

Machines is container of Machine.

Machines is managed as dict. Key is machine name and value is Machine.

Parameters:: parent – parent object which this object belong to

add(machine: str | Machine) → None

add machine as dict key is machine.name and value is machine itself

Parameters:: machine – machine to adding. If machine type is str, create new Machine instance using machine as name.
Raises:: ValueError – If machine is no name

copy() → dict[str, Machine]

get(key: str, default: Any | None = None) → Machine

items()

keys()

values()

class Model

A class managing model.

A model defines a scheduling problem in terms of jobs, machines and resources. Use the solve method to solve the defined scheduling problem using the Amplify Scheduling Engine.

Examples:

from amplify_sched import *
# Define Model
model = Model()
# Define Jobs
model.jobs.add("Job A")
model.jobs.add("Job B")
model.jobs.add("Job C")
model.jobs.add("Job D")
# Define Machines
model.machines.add("Machine X")
model.machines.add("Machine Y")
model.machines.add("Machine Z")
# Add Task to Job
model.jobs["Job A"].append(Task())
model.jobs["Job A"][0].processing_times["Machine X"] = 10
model.jobs["Job A"].append(Task())
model.jobs["Job A"][1].processing_times["Machine Y"] = 20
model.jobs["Job A"].append(Task())
model.jobs["Job A"][2].processing_times["Machine Z"] = 15
model.jobs["Job B"].append(Task())
model.jobs["Job B"][0].processing_times["Machine Y"] = 10
model.jobs["Job B"].append(Task())
model.jobs["Job B"][1].processing_times["Machine Z"] = 20
model.jobs["Job B"].append(Task())
model.jobs["Job B"][2].processing_times["Machine X"] = 15
model.jobs["Job C"].append(Task())
model.jobs["Job C"][0].processing_times["Machine Z"] = 10
model.jobs["Job C"].append(Task())
model.jobs["Job C"][1].processing_times["Machine X"] = 20
model.jobs["Job C"].append(Task())
model.jobs["Job C"][2].processing_times["Machine Y"] = 15
model.jobs["Job D"].append(Task())
model.jobs["Job D"][0].processing_times["Machine Z"] = 10
model.jobs["Job D"].append(Task())
model.jobs["Job D"][1].processing_times["Machine Y"] = 20
model.jobs["Job D"].append(Task())
model.jobs["Job D"][2].processing_times["Machine X"] = 15
# solve using Amplify Scheduling Engine
token = "YOUR TOKEN"
gantt = model.solve(token=token, timeout=1)
# visualize solution
gantt.timeline()

property jobs: Jobs

job list

Jobs is managed as dict. Key is job name and value is Job object.

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].index
0
>>> model.jobs["Job A"].name
'Job A'
>>> model.jobs["Job A"]
{'tasks': [], 'no_wait': None, 'dependent_jobs': []}

property machines: Machines

machine list

Machines is managed as dict. Key is machine name and value is Machine object.

Examples

>>> model = Model()
>>> model.machines.add("Machine A")
>>> model.machines["Machine A"].index
0
>>> model.machines["Machine A"].name
'Machine A'
>>> model.machines["Machine A"]
{'maintenance_times': [], 'buffer_size': None, 'setup_times': []}

property resources: Resources

resource list

Resources is managed as dict. Key is resource name and value is Resource object.

Examples

>>> model = Model()
>>> model.resources.add("Resource A")
>>> model.resources["Resource A"].index
0
>>> model.resources["Resource A"].name
'Resource A'
>>> model.resources["Resource A"]
{'capacity': 1}

solve(token: str, timeout: int, base_url: str = 'https://amplify.fixstars.com/api/schd') → Schedule

solve the scheduling problem

Parameters:

token – token of Amplify Scheduling Engine
timeout – search timeout seconds of Amplify Scheduling Engine
base_url – base url of Amplify Scheduling Engine

Returns:

Solution obtained from Amplify Scheduling Engine

property start: datetime | time

start time of scheduling problem

Examples

>>> model = Model()
>>> model.start = datetime(year=2023, month=1, day=1)
>>> model.start
datetime.datetime(2023, 1, 1, 0, 0)

property time_unit: timedelta

time unit of scheduling problem

Examples

>>> model = Model()
>>> model.time_unit = timedelta(minutes=15)
>>> model.time_unit
datetime.timedelta(seconds=900)

class ProcessingTimes(parent: Task)

ProcessingTimes is container of processing time.

Processing times is managed as dict; key is Machine and value is processing time.

Parameters:: parent – parent object which this object belong to

clear() → None

get(key: Machine | str, default: Any | None = None) → int | timedelta

items(): Return machine and processing time.

keys(): Return machine list registered in processing times.

pop(key: Machine | str, default: Any | None = None) → int | timedelta

popitem() → tuple[Machine, int | timedelta]

values(): Return processing times.

class RequiredResources(parent: Task)

RequiredResources is container of required resource.

RequiredResources is managed as list of Resource.

Parameters:: parent – parent object which this object belong to

append required resource

Parameters:: value – required resource

class Resource(name: str = '')

A class managing a resource.

Parameters:: name – resource name. Defaults to “”

property capacity: int

resource capacity

Capacity must be positive number.

Examples

>>> model = Model()
>>> model.resources.add("Resource A")
>>> model.resources["Resource A"].capacity = 2
>>> model.resources["Resource A"].capacity
2

property index: int

resource index

Examples

>>> model = Model()
>>> model.resources.add("Resource A")
>>> model.resources["Resource A"].index
0
>>> model.resources.add("Resource B")
>>> model.resources["Resource B"].index
1

property name: str

resource name

Examples

>>> model = Model()
>>> model.resources.add("Resource A")
>>> model.resources["Resource A"].name
'Resource A'

class Resources(parent: Model)

Resources is container of resource.

Resources is managed as dict. Key is resource name and value is Resource.

Parameters:: parent – parent object which this object belong to

add(resource: str | Resource) → None

add resource as dict Key is resource.name and value is resource itself.

Parameters:: resource – resource to adding. If resource type is str, create new Resource instance using resource as name.
Raises:: ValueError – If resource is no name.

copy() → dict[str, Resource]

get(key: str, default: Any | None = None) → str | Resource

items()

keys()

values()

class Schedule(result: list[dict[str, int]], status: str, model: Model)

Solution of a scheduling problem. Schedule is generated from solve method of Model.

resource(avail_view: bool = False, width: int | None = None, height: int | None = None) → Figure

Solution resource figure.

Parameters:

avail_view – True to show a timeline for available resources, False for requirements. Defaults to False.
width – The figure width in pixels. Defaults to None.
height – The figure height in pixels. Defaults to None.

Returns:

resource figure

Return type:

plotly.graph_objects.Figure

property status: str: status of the solution

property table: DataFrame: solution in table format

timeline(machine_view: bool = False, separated_by_task: bool = False, width: int | None = None, height: int | None = None) → Figure

Solution timeline figure.

Parameters:

machine_view – True to show a timeline for each machine, False for each job. Defaults to False.
separated_by_task – True to separate GanttChart by process index or False to not separate it. Defaults to False.
width – The figure width in pixels. Defaults to None.
height – The figure height in pixels. Defaults to None.

Returns:

timeline figure

Return type:

plotly.graph_objects.Figure

class SetupTimes(parent: Machine)

SetupTimes is container of setup time.

Setup times is managed as list of tuple. Each element represents one setup time, and each setup time is a tuple with 1 to 3 elements.

Parameters:: parent – parent object which this object belong to

append setup_time

Parameters:: setup_time – setup_time for appending

class Task

A class managing a task.

In a scheduling problem, a task is processed by a machine at a specified processing time. The main target for optimization is the task start time.

add_required_resource(resource: Resource | str) → None

add required resource

Parameters:: resource – required resource

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.resources.add("Resource A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].add_required_resource("Resource A")
>>> model.jobs["Job A"][0].required_resources
['Resource A']

add_transportation_time(transportation_time: int | timedelta, src_machine: Machine | str, dst_machine: Machine | str) → None

add transportation time

add transportation time from a source machine to a destination machine

Parameters:

transportation_time – transportation time
src_machine – source machine
dst_machine – destination machine

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.machines.add("Machine A")
>>> model.machines.add("Machine B")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].add_transportation_time(10, "Machine A", "Machine B")
>>> model.jobs["Job A"][0].transportation_times
[(10, 'Machine A', 'Machine B')]

property deadline: int | datetime | time | None

deadline for this task

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].deadline = 30
>>> model.jobs["Job A"][0].deadline
30

property index: int

task index

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].index
0
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][1].index
1

property processing_times: ProcessingTimes

processing times for this task

Processing times is managed as dict; key is the machine name and value is processing time. During registration, the existence of the machine in the model is checked. Registering a machine name that does not exist in the model will result in a ValueError. If this task is not registered in the model, a ValueError will occur because the existence of the machine cannot be checked.

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.machines.add("Machine A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].processing_times["Machine A"] = 10
>>> model.jobs["Job A"][0].processing_times["Machine A"]
10

property release_time: int | datetime | time | None

release time size for this task

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].release_time = 20
>>> model.jobs["Job A"][0].release_time
20

property required_buffer_size: int | None

required buffer size for this task

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].required_buffer_size = 2
>>> model.jobs["Job A"][0].required_buffer_size
2

property required_resources: RequiredResources

required resources for this task

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.resources.add("Resource A")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].required_resources.append("Resource A")
>>> model.jobs["Job A"][0].required_resources
['Resource A']

property transportation_times: TransportationTimes

transportation time for this task

Examples

>>> model = Model()
>>> model.jobs.add("Job A")
>>> model.machines.add("Machine A")
>>> model.machines.add("Machine B")
>>> model.jobs["Job A"].append(Task())
>>> model.jobs["Job A"][0].transportation_times.append((10, "Machine A", "Machine B"))
>>> model.jobs["Job A"][0].transportation_times
[(10, 'Machine A', 'Machine B')]

class TimeRange(start: datetime | time | int, end: datetime | time | int)

Start and end times expressed as int/datetime.

property end: int | datetime | time: end time of the range

property start: int | datetime | time: start time of the range

class TransportationTimes(parent: Task)

TransportationTimes is container of transportation time.

Transportation times is managed as list of tuple. Each element represents one transportation time, and each transportation time is a tuple with 1 to 3 elements.

Parameters:: parent – parent object which this object belong to

append transportaion_time

Parameters:: value – transportaion_time for appending