Crate rustplex 

Rustplex

rustplex is a linear programming (LP) solver written in Rust, designed with ergonomics and correctness in mind. It provides a type-safe API for modeling optimization problems and solving them using the Simplex algorithm.

Key Features

• Ergonomic API: Use standard Rust operators (+, -, *) to build linear expressions naturally.
• Type Safety: Strongly typed keys (VariableKey, ConstraintKey) prevent mixing up variables and constraints.
• Builder Pattern: Fluent interface for defining variables and constraints.
• Encapsulation: Solvers are isolated from the model definition, allowing for future expansion (e.g., Integer Programming).

Quick Start

Add rustplex to your Cargo.toml. Then, you can define and solve a problem like this:

use rustplex::prelude::*;

fn main() -> Result<(), SolverError> {
    // 1. Create a model
    let mut model = Model::new();

    // 2. Define variables
    let x1 = model.add_variable().name("x1").non_negative().continuous();
    let x2 = model.add_variable().name("x2").bounds(0.0..=10.0).continuous();

    // 3. Set objective: Maximize x1 + x2
    model.set_objective(Maximize, x1 + x2);

    // 4. Add constraints
    // 2*x1 + x2 <= 10
    model.add_constraint(2.0 * x1 + x2).le(10.0);

    // 5. Solve
    let solution = model.solve()?;

    if solution.status() == &SolverStatus::Optimal {
        println!("Objective Value: {}", solution.objective_value().unwrap());
        println!("x1: {}", solution[x1]);
        println!("x2: {}", solution[x2]);
    }

    Ok(())
}

Re-exports

pub use crate::modeling::constraint::Constraint;

pub use crate::modeling::constraint::ConstraintKey;

pub use crate::modeling::constraint::ConstraintSense;

pub use crate::modeling::model::Model;

pub use crate::modeling::objective::Objective;

pub use crate::modeling::objective::ObjectiveSense;

pub use crate::modeling::variable::Variable;

pub use crate::modeling::variable::VariableKey;

pub use crate::modeling::variable::VariableType;

Modules

error

modeling

prelude

The Rustplex Prelude

Structs

LinearExpr

A linear expression stored as a sorted sparse vector. Invariants:

SolverConfig

Configuration settings for the Simplex Solver.

SolverSolution

The result of a solved optimization model.

Enums

SolverStatus

Represents the terminal state of the solver execution.