Covering array
Description:
Returns a t-wise covering array: a set of valid configurations covering every satisfiable combination of t feature selections (pairwise for t = 2).
Application:
Generates a small set of products to test so that every valid combination of t feature selections is exercised at least once (combinatorial interaction testing).
Example:
For the pairwise case (t = 2) a model with hundreds of configurations can be covered with around ten of them.
Code Examples
Command line usage
flamapy covering_array "path/to/feature/model" --t 2 --seed 42
Python easy to use facade usage
from flamapy.interfaces.python.flamapy_feature_model import FLAMAFeatureModel
# Load the feature model
fm = FLAMAFeatureModel("path/to/feature/model")
# Pairwise covering array; the seed makes the result reproducible
result = fm.covering_array(t=2, seed=42)
print(result)
Python flamapy framework usage
from flamapy.core.discover import DiscoverMetamodels
# Initialize the discover metamodel
dm = DiscoverMetamodels()
# Call the operation. Transformations will be automatically executed
result = dm.use_operation_from_file("PySATCoveringArray", "path/to/feature/model")
print(result)
Python flamapy framework ADVANCED usage
from flamapy.core.discover import DiscoverMetamodels
# Initialize the discover metamodel
dm = DiscoverMetamodels()
# Get the fm metamodel representation using the transformation
# required to get to the fm metamodel
feature_model = dm.use_transformation_t2m("path/to/feature/model", 'fm')
# Manually call a M2M transformation to PySAT
sat_model = dm.use_transformation_m2m(feature_model, "pysat")
# Get the operation
operation = dm.get_operation(sat_model, 'PySATCoveringArray')
# Set the interaction strength and the random seed
operation.set_t(2)
operation.set_seed(42)
# Execute the operation
operation.execute(sat_model)
# Get and print the result
result = operation.get_result()
print(result)
Facade signature: covering_array(self, t: int = 2, seed: int = None)
Inputs:
| name | type | required | default |
|---|---|---|---|
t |
int | no | 2 |
seed |
int | no | None |
Default backend: sat
Implemented by:
| plugin | exact | scale limit |
|---|---|---|
| pysat_metamodel | yes | — |