Enum CumulativeExplanationType

pub enum CumulativeExplanationType {
    Naive,
    BigStep,
    PointWise,
}

Determines what type of explanation is used for the cumulative constraint based on the explanations described in Section 4.5.1 and 4.5.2 of [1].

For the explanations of conflicts and conflicts, we different between 3 types of explanations:

• The naive explanation (see CumulativeExplanationType::Naive)
• The bigstep explanation (see CumulativeExplanationType::BigStep)
• The pointwise explanation (see CumulativeExplanationType::PointWise)

Bibliography

[1] A. Schutt, Improving scheduling by learning. University of Melbourne, Department of Computer Science and Software Engineering, 2011.

Variants

Naive

The naive explanation approach simply uses the current bounds of the profile and the propagated task in the explanation.

BigStep

The default; lifts the explanation to create an explanation which uses the bounds which would cause the tasks in the profile to have mandatory parts in the range of the propagating profile.

PointWise

Creates an explanation over a set of time-points;

Propagations

Note that we currently do not generate chains of profiles which cause a propagation. This means that the explanation only concerns a single profile; the selected time-points for a propagation of task i are constructed as follows in the case of a lower-bound propagation: [profile.start, profile.start + i.process_time, profile.start + (2 * i.processing_time), ..., profile.end]. Thus, if the profile is shorter than i.processing_time, two explanations are generated for the time-points profile.start and profile.end.

Conflicts

For conflicts we follow the work by Schutt (see the documentation for CumulativeExplanationType) and select the middle point in the profile as the point used for the explanation.

Trait Implementations

impl Clone for CumulativeExplanationType

fn clone(&self) -> CumulativeExplanationType

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CumulativeExplanationType

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CumulativeExplanationType

fn default() -> CumulativeExplanationType

Returns the “default value” for a type.

impl Display for CumulativeExplanationType

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for CumulativeExplanationType