Saving & loading jobs

This example demonstrates how jobs can be saved to files and then recovered later, allowing for the retrieval of results between sessions.

import lightworks as lw
from lightworks import remote

try:
    remote.token.load("main_token")
except remote.TokenError:
    print(
        "Token could not be automatically loaded, this will need to be "
        "manually configured."
    )

We’ll start by generating a random task to submit to the system.

qpu = remote.QPU("Artemis")

circuit = lw.Unitary(lw.random_unitary(6))
input_state = lw.State([1, 0, 0, 1, 0, 0])
n_samples = 1000

sampler = lw.Sampler(circuit, input_state, n_samples)

And then run this on the target QPU to generate a job. The ID of this can then be printed.

job = qpu.run(sampler)
print(f"Job ID: {job.job_id}")

Job ID: 17769

Saving

Once a job is created, this can then be saved as a json file using the provided method.

job.save_to_file("demo_job", allow_overwrite=True)

Loading

To recover a job, the load_job_from_file method is used, providing the name of the file to it. It can be seen how the job ID is correctly recovered after saving.

loaded_job = remote.load_job_from_file("demo_job")
print(f"Job ID: {loaded_job.job_id}")

Job ID: 17769

The return of this method is a Job, which can be used in the same way as any other job. For example, results can be downloaded and plotting using the code below.

loaded_job.wait_until_complete()

results = loaded_job.get_result()
results.plot()