sweetpea.core.generate.utility module

This module provides the types and common functions that are used across the various submodules of sweetpea.core.generate.

class sweetpea.core.generate.utility.AssertionType(value)

Bases: enum.Enum

The three supported variants of CNF assertion.

EQ = 1

Assert k == n.

LT = 2

Assert k < n.

GT = 3

Assert k > n.

static from_json(s)

Converts a JSON string to an AssertionType.

Parameters

s (str) –

Return type

sweetpea.core.generate.utility.AssertionType

class sweetpea.core.generate.utility.GenerationRequest(assertion_type, k, boolean_values)

Bases: tuple

A request to generate a CNF.

Create new instance of GenerationRequest(assertion_type, k, boolean_values)

Parameters
property assertion_type

The variant of assertion to make.

property k

The k value.

property boolean_values

A list of variables to use in generation.

static from_json(data)

Converts a JSON object to a GenerationRequest.

Parameters

data (Dict[str, Any]) –

Return type

sweetpea.core.generate.utility.GenerationRequest

class sweetpea.core.generate.utility.SampleType(value)

Bases: enum.Enum

The supported methods of interacting with SweetPea core.

Uniform = 1

Uniform sampling of a CNF formula.

NonUniform = 2

Non-uniform sampling of a CNF formula.

IsSatisfiable = 3

Test whether a CNF formula is satisfiable.

static from_json(s)

Converts a JSON string to a SampleType.

Parameters

s (str) –

Return type

sweetpea.core.generate.utility.SampleType

class sweetpea.core.generate.utility.ProblemSpecification(sample_type, sample_count, fresh, support, cnf, requests)

Bases: tuple

A specification of a complete SweetPea problem to be solved.

Create new instance of ProblemSpecification(sample_type, sample_count, fresh, support, cnf, requests)

Parameters
property sample_type

The type of sample to produce.

property sample_count

The number of samples to take.

property fresh

Alias for field number 2

property support

The length of the support set.

property cnf

The CNF formula to sample.

property requests

A list of requests to make with regard to the CNF formula.

static from_json(data)

Converts a JSON object to a ProblemSpecification.

Parameters

data (Dict[str, Any]) –

Return type

sweetpea.core.generate.utility.ProblemSpecification

class sweetpea.core.generate.utility.Solution(assignment, frequency)

Bases: tuple

The result of a generation.

Create new instance of Solution(assignment, frequency)

Parameters

  • assignment (List[int]) –

  • frequency (int) –

property assignment

Alias for field number 0

property frequency

Alias for field number 1

sweetpea.core.generate.utility.combine_and_save_cnf(filename, initial_cnf, fresh, support, generation_requests)

Combines a base CNF formula with the augmentations specified by the list of GenerationRequests, merges those formulas, then saves the result to a file at the given path.

Parameters
sweetpea.core.generate.utility.combine_cnf_with_requests(initial_cnf, fresh, support, generation_requests)

Combines a base CNF with a new CNF formed from the given GenerationRequests.

Parameters
Return type

sweetpea.core.cnf.CNF

sweetpea.core.generate.utility.save_cnf(filename, cnf, fresh=None, support=None)

Writes a CNF formula to a file at the given path.

Parameters
sweetpea.core.generate.utility.temporary_cnf_file(base_path=PosixPath('.'))

Returns a pathlib.Path to a new, local file in the directory of the given path with a .cnf suffix. When used as a context manager (recommended), the file will be deleted when it leaves the context scope.

Parameters

base_path (pathlib.Path) –

Return type

Iterator[pathlib.Path]