interval

Interval(feature, left_endpoint, right_endpoint, min_value, max_value)

Represents an interval for a specific feature.

The interval belongs to one equivalence class.

Attributes:

feature: int Index of the feature to which the interval belongs.

IntervalEndpoint

Indicates whether the interval is left-open or left-closed.

IntervalEndpoint

Indicates whether the interval is right-open or right-closed.

int | float

Lower bound of the interval.

int | float

Upper bound of the interval.

Initializes an Interval object.

Parameters:

Name	Type	Description	Default
feature	int	Index of the feature to which the interval belongs.	required
left_endpoint	IntervalEndpoint	Left endpoint type ('(' for open, '[' for closed).	required
right_endpoint	IntervalEndpoint	Right endpoint type (')' for open, ']' for closed).	required
min_value	float	Lower bound of the interval.	required
max_value	float	Upper bound of the interval.	required

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

def __init__(
    self,
    feature: int,
    left_endpoint: IntervalEndpoint,
    right_endpoint: IntervalEndpoint,
    min_value: float,
    max_value: float,
) -> None:
    """Initializes an Interval object.

    Args:
        feature: Index of the feature to which the interval belongs.
        left_endpoint: Left endpoint type ('(' for open, '[' for closed).
        right_endpoint: Right endpoint type
            (')' for open, ']' for closed).
        min_value: Lower bound of the interval.
        max_value: Upper bound of the interval.
    """
    self.feature = feature
    self.left_endpoint = left_endpoint
    self.right_endpoint = right_endpoint
    self.min_value = min_value
    self.max_value = max_value

__str__()

Returns a string representation of the interval.

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

def __str__(self) -> str:
    """Returns a string representation of the interval."""
    return (
        self.left_endpoint.value
        + str(self.min_value)
        + ","
        + str(self.max_value)
        + self.right_endpoint.value
    )

is_closed()

Checks if the interval is fully closed [a, b].

Returns:

Type	Description
bool	True if both endpoints are closed.

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

def is_closed(self) -> bool:
    """Checks if the interval is fully closed [a, b].

    Returns:
        True if both endpoints are closed.
    """
    return (
        self.left_endpoint == IntervalEndpoint.LEFT_CLOSED
        and self.right_endpoint == IntervalEndpoint.RIGHT_CLOSED
    )

is_open()

Checks if the interval is fully open (a, b).

Returns:

Type	Description
bool	True if both endpoints are open.

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

def is_open(self) -> bool:
    """Checks if the interval is fully open (a, b).

    Returns:
        True if both endpoints are open.
    """
    return (
        self.left_endpoint == IntervalEndpoint.LEFT_OPEN
        and self.right_endpoint == IntervalEndpoint.RIGHT_OPEN
    )

is_right_open()

Checks if the interval is right-open [a, b).

Returns:

Type	Description
bool	True if left is closed and right is open.

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

def is_right_open(self) -> bool:
    """Checks if the interval is right-open [a, b).

    Returns:
        True if left is closed and right is open.
    """
    return (
        self.left_endpoint == IntervalEndpoint.LEFT_CLOSED
        and self.right_endpoint == IntervalEndpoint.RIGHT_OPEN
    )

is_left_open()

Checks if the interval is left-open (a, b].

Returns:

Type	Description
bool	True if left is open and right is closed.

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

def is_left_open(self) -> bool:
    """Checks if the interval is left-open (a, b].

    Returns:
        True if left is open and right is closed.
    """
    return (
        self.left_endpoint == IntervalEndpoint.RIGHT_CLOSED
        and self.right_endpoint == IntervalEndpoint.LEFT_OPEN
    )

is_subset(interval_a, interval_b) staticmethod

Determines which interval is a subset of the other.

Parameters:

Name	Type	Description	Default
interval_a	Interval	First interval to compare.	required
interval_b	Interval	Second interval to compare.	required

Returns:

Type	Description
Interval | None	The superset interval if one contains the other,
Interval | None	otherwise None.

Source code in src/flowcean/testing/generator/ddtig/domain/model_analyser/surrogate/interval.py

@staticmethod
def is_subset(
    interval_a: Interval,
    interval_b: Interval,
) -> Interval | None:
    """Determines which interval is a subset of the other.

    Args:
        interval_a: First interval to compare.
        interval_b: Second interval to compare.

    Returns:
        The superset interval if one contains the other,
        otherwise None.
    """
    ordered = Interval._order_by_bounds(interval_a, interval_b)
    if ordered is None:
        return None

    interval_large, interval_small = ordered

    # Case 1: Strict containment
    if (
        interval_large.min_value < interval_small.min_value
        and interval_large.max_value > interval_small.max_value
    ):
        return interval_large

    # Case 2: Same lower bound, larger upper bound
    if (
        interval_large.min_value == interval_small.min_value
        and interval_large.max_value > interval_small.max_value
    ):
        left_ok = (
            interval_small.left_endpoint == IntervalEndpoint.LEFT_OPEN
            or interval_large.left_endpoint == IntervalEndpoint.LEFT_CLOSED
        )
        return interval_large if left_ok else None

    # Case 3: Smaller lower bound, same upper bound
    if (
        interval_large.min_value < interval_small.min_value
        and interval_large.max_value == interval_small.max_value
    ):
        right_ok = (
            interval_small.right_endpoint == IntervalEndpoint.RIGHT_OPEN
            or interval_large.right_endpoint
            == IntervalEndpoint.RIGHT_CLOSED
        )
        return interval_large if right_ok else None

    # Case 4: Same bounds
    if (
        interval_a.min_value == interval_b.min_value
        and interval_a.max_value == interval_b.max_value
    ):
        return Interval._same_bounds_superset(interval_a, interval_b)
    return None

IntervalEndpoint

Bases: Enum

Enum representing the types of interval endpoints.