Clp Ruby

Clp - linear programming solver - for Ruby

Check out Opt for a high-level interface

Installation

First, install Clp. For Homebrew, use:

brew install clp

And for Ubuntu, use:

sudo apt-get install coinor-libclp1

Then add this line to your application’s Gemfile:

gem "clp"

Getting Started

The API is fairly low-level at the moment

Load a problem

model =
  Clp.load_problem(
    sense: :minimize,
    start: [0, 3, 6],
    index: [0, 1, 2, 0, 1, 2],
    value: [2, 3, 2, 2, 4, 1],
    col_lower: [0, 0],
    col_upper: [1e30, 1e30],
    obj: [8, 10],
    row_lower: [7, 12, 6],
    row_upper: [1e30, 1e30, 1e30]
  )

Solve

model.solve

Write the problem to an MPS file (requires Clp 1.17.2+)

model.write_mps("hello.mps")

Read a problem from an MPS file

model = Clp.read_mps("hello.mps")

Reference

Set the log level

model.solve(log_level: 4)

Set the time limit in seconds

model.solve(time_limit: 30)

History

View the changelog

Contributing

Everyone is encouraged to help improve this project. Here are a few ways you can help:

• Report bugs
• Fix bugs and submit pull requests
• Write, clarify, or fix documentation
• Suggest or add new features

To get started with development:

git clone https://github.com/ankane/clp-ruby.git
cd clp-ruby
bundle install
bundle exec rake test