Installing OR-Tools .Net from Source on Windows

Introduction

This guide explains how to install OR-Tools from source, with support for .Net, on Windows.

Unless you plan to modify the source code or use a third-party solver with OR-Tools, we recommend the binary installation.

Although these instructions might also work on other Windows variants, we have only tested them on machines meeting the following requirements: Windows 10 64-bit (x86_64) with:

• Microsoft Visual Studio [Community] 2022
• Microsoft Visual Studio [Community] 2019

Note: OR-Tools only supports the x86-64 (also known as amd64) architecture.

Prerequisites

The following sections describe the prerequisites for installing OR-Tools.

Visual Studio

To build and run OR-Tools on Windows, you must have Visual Studio 2019 or later installed on your computer with the C++ toolset for Visual Studio.

You can find more details here.

To build OR-Tools programs from the command line you must use a x64 Native Tools Command Prompt (not the Developer Command Prompt).

You can find more details here.

Git

Git, which can be downloaded from https://git-scm.com/.

CMake

CMake (>= 3.18), which can be downloaded from https://www.cmake.org/download. When installing CMake, select the option for a command-line accessible cmake.

.NET Core 3.1 SDK

You must install the package .NET Core 3.1 SDK version 3.1.100 or higher from the following location: sdk-3.1.423-windows-x64-installer

.Net 6.0 SDK

You must install the package .NET 6.0 SDK from the following location: sdk-6.0.401-windows-x64-installer

Download the source code

There are two distinct branches of the OR-Tools source code on GitHub: stable and main.

The stable branch has been thoroughly tested and should work flawlessly on all supported platforms.
The main branch is where the latest updates and improvements have been applied; it's more current, but less stable.

Download the stable source code

You can get the stable source code for OR-Tools in either of the following ways:

• Clone the stable branch by entering:

  git clone https://github.com/google/or-tools
  

• Download the latest release in a compressed file, by clicking the Clone or download button in GitHub.

Warning: The full path to the installation directory (where you extract the files) must not contain any spaces.

Download the main source code

To retrieve the source code from the main branch, enter:

git clone -b main https://github.com/google/or-tools

Download previous releases

You can get the source code for previous releases in either of the following ways:

• Download a previous release from the GitHub release page.

• Assuming you have already created a local repository (by git clone), you can check out a specific release using a Git tag. For example, to work with the v9.4 release instead of the main branch, enter the following commands in your local repo:

  git fetch --all --tags --prune
  git checkout tags/v9.4 -v v9.4
  

Build third parties

Before building OR-Tools, you'll need to build the required third party software.

Open a terminal and navigate to the directory where you extracted the files. Then enter:

tools\make third_party

Using SCIP

Since v7.8, SCIP is now integrated so you won't have to install it manually.

Warning: While OR-Tools ships with SCIP, please consult the SCIP license to ensure that you are complying with it.

Using Gurobi

Gurobi is now pre-integrated. When needed, at runtime, OR-Tools will search for the Gurobi shared library in the default install path of the Gurobi installers on MAC OS X and Windows, or by using the GUROBI_HOME environment variable.

Using an optional third-party MIP solver

You can also use OR-Tools with any of the following optional third-party MIP solvers whose support is disabled by default:

• CPLEX
• GLPK (Linux and MacOS only)
• XPRESS Solver

To configure OR-Tools to use one of these solvers, do the following steps:

1. Install the optional solver following the vendor instruction.
2. Open Makefile.local and add the path to the directory where you have installed the solver. For example, for CPLEX you would add this:

   WINDOWS_CPLEX_DIR=c:/Program~1/CPLEX_STUDIO1210

Build the source code

To build the source code, open a terminal and navigate to the directory where you extracted the files. Then enter the following command to compile OR-Tools:

tools\make dotnet

Test the source code

You can check that everything is running correctly by entering:

tools\make test_dotnet

This runs a selection of examples for OR-Tools. If all the examples run successfully, you are ready to get started with OR-Tools.

Cleaning the build files

If you need to re-install OR-Tools, the command:

tools\make clean_third_party

will remove all compiled dependencies and Makefile.local. This can be useful for resetting to a clean state.

Then re-enter the commands:

tools\make third_party

tools\make dotnet