fuzzy_dl_owl2.fuzzydl.concept.sigma_count
A structural representation of a sigma-count concept within fuzzy description logic that evaluates constraints based on the quantity of role fillers satisfying specific conditions.
Description
Sigma-count concepts serve to quantify the number of role fillers that satisfy a specific condition, effectively bridging fuzzy set theory with description logic structures. By encapsulating a variable, a target individual, a collection of reference individuals, a role identifier, and a specific concept, the implementation allows for the evaluation of whether the count of related entities meets a fuzzy constraint. The design ensures that these logical components can be safely duplicated through deep cloning, which is essential for maintaining state integrity during complex reasoning tasks. Furthermore, the implementation provides robust hashing and string representation capabilities, enabling instances to be used effectively within hash-based collections and facilitating readable debugging output.
Classes
This class represents a sigma-count concept within fuzzy description logic, serving as a structural representation for evaluating constraints based on the quantity of role fillers. It defines a condition where a target individual is considered satisfied if the number of related entities—connected via a specific role and conforming to a particular concept—falls within a fuzzy set determined by a collection of reference individuals. To use this class, instantiate it with a variable for the count, the target individual, the list of reference individuals, the role name, and the concept to be evaluated. The object provides methods to access these internal components and a cloning utility to create deep copies of the instance. |
Module Contents
UML Class Diagram for SigmaCount
- class SigmaCount(
- var: fuzzy_dl_owl2.fuzzydl.milp.variable.Variable,
- ind: fuzzy_dl_owl2.fuzzydl.individual.individual.Individual,
- inds: list[fuzzy_dl_owl2.fuzzydl.individual.individual.Individual],
- role: str,
- concept: fuzzy_dl_owl2.fuzzydl.concept.concept.Concept,
This class represents a sigma-count concept within fuzzy description logic, serving as a structural representation for evaluating constraints based on the quantity of role fillers. It defines a condition where a target individual is considered satisfied if the number of related entities—connected via a specific role and conforming to a particular concept—falls within a fuzzy set determined by a collection of reference individuals. To use this class, instantiate it with a variable for the count, the target individual, the list of reference individuals, the role name, and the concept to be evaluated. The object provides methods to access these internal components and a cloning utility to create deep copies of the instance.
- Parameters:
variable (Variable) – The variable associated with the sigma-count concept, used for counting the number of role fillers that satisfy the concept C.
individual (Individual) – The individual for which the sigma-count concept is being evaluated.
individuals (list[Individual]) – The set of individuals ${a_1, a_2, dots, a_n}$ considered in the fuzzy concrete concept $D$ for the sigma-count evaluation.
role (str) – The relationship identifier ‘r’ used in the sigma-count expression to connect the individual to the fillers being counted.
concept (Concept) – The concept C that role fillers must satisfy to be included in the sigma-count.
- __hash__() int
Return a hash value for this object, computed from its string representation. This approach ensures that the hash value reflects the structural identity of the object without relying on cached values or additional methods. The hash is derived from the output of the __str__ method, which provides a consistent and unique representation of the concept’s structure. This implementation does not utilize any internal caching mechanism and directly computes the hash each time it is called.
- Returns:
An integer hash value representing the structural identity of this object.
- Return type:
int
- __repr__() str
Returns the official string representation of the instance by delegating directly to the informal string conversion logic. This approach ensures that the output displayed in interactive sessions or logs is identical to the user-facing string format. The method performs no state modifications and depends entirely on the behavior of the __str__ method to generate the resulting string.
- Returns:
The string representation of the object, identical to the output of str().
- Return type:
str
- __str__() str
Returns a human-readable string representation of the SigmaCount instance formatted as a functional expression. The output string follows the pattern ‘sigma-count(…)’, incorporating the object’s variable, individual, individuals, role, and concept attributes as comma-separated arguments. This method is intended for display purposes and does not modify the object’s state.
- Returns:
A string representation of the object, formatted as a sigma-count function call containing the variable, individual, individuals, role, and concept attributes.
- Return type:
str
- clone() Self
Creates and returns a deep copy of the current SigmaCount instance. The method recursively clones the variable, individual, and concept attributes, and generates a new list containing clones of all elements within the individuals collection. The role attribute is passed by reference rather than being cloned. This operation has no side effects on the original object, ensuring that the returned instance is independent with respect to its deep-copied components.
- Returns:
A new instance of SigmaCount that is a deep copy of the current object.
- Return type:
Self
- get_concept() fuzzy_dl_owl2.fuzzydl.concept.concept.Concept
Returns the Concept object associated with the current SigmaCount instance. This method acts as a simple accessor, retrieving the value of the concept attribute without modifying the object’s internal state. If the attribute has not been set, this method will raise an AttributeError.
- Returns:
The Concept object associated with this instance.
- Return type:
- get_individual() fuzzy_dl_owl2.fuzzydl.individual.individual.Individual
Retrieves the Individual entity associated with the current SigmaCount instance. This accessor method returns the reference to the stored object without causing any side effects or modifying the internal state.
- Returns:
The Individual instance associated with this object.
- Return type:
- get_individuals() list[fuzzy_dl_owl2.fuzzydl.individual.individual.Individual]
Retrieves the collection of Individual objects managed by the SigmaCount instance. Since this method returns a direct reference to the internal list, any in-place modifications to the returned list will alter the state of the object.
- Returns:
A list of the individuals associated with this instance.
- Return type:
list[Individual]
- get_role() str
Retrieves the string value assigned to the role attribute of the current instance. This accessor method provides read-only access to the specific role or category associated with the SigmaCount object without modifying its internal state. It assumes the attribute has been properly initialized; accessing this method on an instance where the attribute is missing will result in an AttributeError.
- Returns:
The role associated with the instance.
- Return type:
str
- get_variable() fuzzy_dl_owl2.fuzzydl.milp.variable.Variable
Retrieves the Variable instance associated with this SigmaCount object. This method acts as a simple accessor, returning the reference to the internal variable attribute without modifying the state of the object. It allows external code to inspect which variable is being tracked or aggregated by the counter.
- Returns:
The Variable instance stored in the variable attribute.
- Return type:
- individuals: list[fuzzy_dl_owl2.fuzzydl.individual.individual.Individual]
- role: str