https://github.com/dandxy89/lp_parser_rs

Rust LP File Parser and Diff tool
https://github.com/dandxy89/lp_parser_rs

diff integer-programming linear-programming lp lpfile nom parser rust

Last synced: 15 days ago
JSON representation

Rust LP File Parser and Diff tool

Host: GitHub
URL: https://github.com/dandxy89/lp_parser_rs
Owner: dandxy89
License: apache-2.0
Created: 2023-11-10T19:13:01.000Z (about 2 years ago)
Default Branch: main
Last Pushed: 2025-03-24T22:06:26.000Z (8 months ago)
Last Synced: 2025-04-10T16:55:27.046Z (8 months ago)
Topics: diff, integer-programming, linear-programming, lp, lpfile, nom, parser, rust
Language: Linear Programming
Homepage: https://docs.rs/lp_parser_rs/latest/lp_parser_rs/
Size: 4.6 MB
Stars: 3
Watchers: 3
Forks: 1
Open Issues: 1
Metadata Files:
- Readme: README.md
- License: LICENSE-APACHE
- Codeowners: .github/CODEOWNERS

Awesome Lists containing this project

awesome-rust-formalized-reasoning - lp_parser_rs - LP file parser. (Projects / Libraries)

README

          # Rust LP File Parser, Writer, and Diff Tool

[![Cargo Test](https://github.com/dandxy89/congenial-enigma/actions/workflows/cargo_test.yml/badge.svg)](https://github.com/dandxy89/congenial-enigma/actions/workflows/cargo_test.yml)

[![Crates.io](https://img.shields.io/crates/v/lp_parser_rs.svg)](https://crates.io/crates/lp_parser_rs)

[![Documentation](https://docs.rs/lp_parser_rs/badge.svg)](https://docs.rs/lp_parser_rs/)

[![PyPI version](https://badge.fury.io/py/parse-lp.svg)](https://badge.fury.io/py/parse-lp)

[![PyPI Downloads](https://static.pepy.tech/personalized-badge/parse-lp?period=total&units=NONE&left_color=BLACK&right_color=GREEN&left_text=downloads)](https://pepy.tech/projects/parse-lp)

## Overview

A robust Rust library for parsing, modifying, and writing Linear Programming (LP) files. Built on the [NOM](https://docs.rs/nom/latest/nom/) parsing framework, this crate provides comprehensive support for the LP file format with the ability to parse, programmatically modify, and regenerate LP files according to major industry specifications.

### Supported Specifications

- [IBM CPLEX v22.1.1](https://www.ibm.com/docs/en/icos/22.1.1?topic=cplex-lp-file-format-algebraic-representation)

- [FICO Xpress](https://www.fico.com/fico-xpress-optimization/docs/dms2020-03/solver/optimizer/HTML/chapter10_sec_section102.html)

- [Gurobi](https://www.gurobi.com/documentation/current/refman/lp_format.html)

- Mosek

## Features

### Core Functionality

- **Problem Definition**

  - Problem name and sense specification

  - Single and multi-objective optimisation support

  - Comprehensive constraint handling

- **Variable Support**

  - Integer, general, bounded, free, semi-continuous variables

- **LP File Writing and Modification**

  - Generate LP files from parsed problems

  - Modify objectives, constraints, and variables programmatically

  - Round-trip compatibility (parse → modify → write → parse)

  - Maintain proper LP format specifications

### Advanced Features

- **LP File Comparison (`diff` feature)**

  - Identify added, removed, and modified elements

  - Useful for model version control and validation

- **Serialisation (`serde` feature)**

  - Full serialisation support for all model structures

  - Compatible with various data formats

  - Enables integration with other tools and systems

## Quick Start

### Installation

Add to your `Cargo.toml`:

```toml

[dependencies]

lp_parser_rs = "2.4.1"

```

### Basic Usage

Clone and run with a sample file:

```bash

git clone https://github.com/dandxy89/lp_parser_rs.git

# Parse a single LP file

cargo run --bin lp_parser --release -- {{ /path/to/your/file.lp }}

# Compare two LP files (enabling the 'diff' feature)

cargo run --bin lp_parser --release --features diff -- {{ /path/to/your/file.lp }} {{ /path/to/your/other/file.lp }}

```

Using the library directly:

```rust

use lp_parser_rs::{parser::parse_file, problem::LpProblem};

use std::path::Path;

fn main() -> Result<(), Box> {

    // Parse LP file content

    let content = parse_file(Path::new("problem.lp"))?;

    // Parse into LP problem structure

    let problem = LpProblem::parse(&content)?;

    // Access problem components

    println!("Problem name: {:?}", problem.name());

    println!("Objective count: {}", problem.objective_count());

    println!("Constraint count: {}", problem.constraint_count());

    println!("Variable count: {}", problem.variable_count());

    Ok(())

}

```

### LP File Writing and Modification

```rust

use lp_parser_rs::{problem::LpProblem, writer::write_lp_string, model::*};

fn main() -> Result<(), Box> {

    // Parse an existing LP file

    let lp_content = std::fs::read_to_string("problem.lp")?;

    let mut problem = LpProblem::parse(&lp_content)?;

    // Modify objectives

    problem.update_objective_coefficient("profit", "x1", 5.0)?;

    problem.rename_objective("profit", "total_profit")?;

    // Modify constraints

    problem.update_constraint_coefficient("capacity", "x1", 2.0)?;

    problem.update_constraint_rhs("capacity", 200.0)?;

    problem.rename_constraint("capacity", "production_limit")?;

    // Modify variables

    problem.rename_variable("x1", "production_a")?;

    problem.update_variable_type("production_a", VariableType::Integer)?;

    // Write back to LP format

    let modified_lp = write_lp_string(&problem)?;

    std::fs::write("modified_problem.lp", modified_lp)?;

    Ok(())

}

```

### Enable Optional Features

```toml

[dependencies]

lp_parser_rs = { version = "2.4.1", features = ["serde", "diff"] }

```

## API Reference

### Problem Modification Methods

The `LpProblem` struct provides comprehensive methods for modifying LP problems:

#### Objective Modifications

- `update_objective_coefficient(objective_name, variable_name, coefficient)` - Update or add a coefficient in an objective

- `rename_objective(old_name, new_name)` - Rename an objective

- `remove_objective(objective_name)` - Remove an objective

#### Constraint Modifications

- `update_constraint_coefficient(constraint_name, variable_name, coefficient)` - Update or add a coefficient in a constraint

- `update_constraint_rhs(constraint_name, new_rhs)` - Update the right-hand side value

- `rename_constraint(old_name, new_name)` - Rename a constraint

- `remove_constraint(constraint_name)` - Remove a constraint

#### Variable Modifications

- `rename_variable(old_name, new_name)` - Rename a variable across all objectives and constraints

- `update_variable_type(variable_name, new_type)` - Change variable type (Binary, Integer, etc.)

- `remove_variable(variable_name)` - Remove a variable from all objectives and constraints

### Writing LP Files

```rust

use lp_parser::writer::{write_lp_string, write_lp_string_with_options, LpWriterOptions};

// Write with default options

let lp_content = write_lp_string(&problem)?;

// Write with custom options

let options = LpWriterOptions {

    include_problem_name: true,

    max_line_length: 80,

    decimal_precision: 6,

    include_section_spacing: true,

};

let lp_content = write_lp_string_with_options(&problem, &options)?;

```

## Development

### Testing

The project uses snapshot testing via `insta` for reliable test management:

```bash

# Run all tests with all features enabled

cargo insta test --all-features

# Review snapshot changes

cargo insta review

```

## Test Data Sources

The test suite includes data from various open-source projects:

- [Jplex](https://github.com/asbestian/jplex/blob/main/instances/afiro.lp)

- [LPWriter.jl](https://github.com/odow/LPWriter.jl/blob/master/test/model2.lp)

- [Lp-Parser](https://github.com/aphi/Lp-Parser)

## Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

ecosyste.ms

Data

Tools

Indexes

Applications

Experiments

Awesome

https://github.com/dandxy89/lp_parser_rs

Awesome Lists containing this project

README