dimod#

dimod is a shared API for samplers. It provides:

  • classes for quadratic models—such as the binary quadratic model (BQM) class that contains Ising and QUBO models used by samplers such as the D-Wave system—and higher-order (non-quadratic) models.

  • reference examples of samplers and composed samplers.

  • abstract base classes for constructing new samplers and composed samplers.

(For explanations of the terminology, see the Ocean glossary.)

Example Usage#

Find all solutions to a two-variable BQM using dimod’s ExactSolver reference sampler, a brute-force solver useful for testing code on small problems.

>>> import dimod
...
>>> # Construct a problem
>>> bqm = dimod.BinaryQuadraticModel({0: -1, 1: 1}, {(0, 1): 2}, 0.0, dimod.BINARY)
...
>>> # Use dimod's brute force solver to solve the problem
>>> sampleset = dimod.ExactSolver().sample(bqm)
>>> print(sampleset)
   0  1 energy num_oc.
1  1  0   -1.0       1
0  0  0    0.0       1
3  0  1    1.0       1
2  1  1    2.0       1
['BINARY', 4 rows, 4 samples, 2 variables]

Documentation#

Date:

Jan 16, 2024

Note

This documentation is for the latest version of dimod. Documentation for the version currently installed by dwave-ocean-sdk is here: dimod.

Indices and tables#