The Gurobi Optimizer is a state-of-the-art solver for mathematical programming. The solvers in the Gurobi Optimizer were designed from the ground up to exploit modern architectures and multi-core processors.
For more information on Gurobi products and services, see the Gurobi website. The user must submit a model in GAMS format to solve an optimization problem. For security purposes, the model submitted must adhere to the following conventions: It must be self contained, i. It may not execute external programs, i. No file creation, i. Other files created in the GAMS model file will be deleted. By default, the NEOS Server limits the amount of output generated in the listing file by turning off the symbol and unique element list, symbol cross references, and restricting the rows and columns listed to zero.
This behavior can be changed by specifying the appropriate options in the model file. See the documentation on GAMS output for further information. You may optionally submit an options file if you wish to override the default parameter settings for the solver. Therefore, any model that specifies a different options file will not work as intended. The GDX file is an optional file for inputs. It will be renamed in.
Mixed-Integer Programming (MIP) – A Primer on the Basics
More than 2, companies in over 40 industries turn data into smarter decisions with Gurobi. The Gurobi Optimizer enables users to state their toughest business problems as mathematical models and then finds the best solution out of trillions of possibilities. Gurobi Optimizer can also become a decision-making assistant, guiding the choices of a skilled expert or even run in fully autonomous mode without human intervention.
Gurobi Version 9. We are happy to help you benchmark your models with Gurobi v9. Learn more about Benchmarks. Deterministic parallel, non-traditional search, heuristics, solution improvement, cutting planes, and symmetry breaking.
Whether you are building a new model or migrating existing setup, Gurobi delivers superior performance. All object and matrix-oriented interfaces are implemented as lightweight APIs. You can learn more on our Technical Features and Detail page. Deploy your model where and how you want. One user can solve a single model on one machine. Many users can solve multiple models using many machines. Models can also be solved locally or on an internal or public cloud. Customers have direct access to PhD-level optimization experts with years of experience working with commercial models.
With Gurobi, you get answers when you need them, not in days or weeks. Python users can choose to use the Anaconda Python distribution with pre-built libraries to support application development, Spyder for graphical development, and Jupyter for notebook-style development. Additionally, we provide an interactive interface that uses Python for quick testing. Our licenses may be used for both development and deployment. Gurobi offers a wide range of licensing options to fit your needs.Solving Simple Stochastic Optimization Problems with Gurobi
Switching from another solver. Please email sales gurobi. Search for: Search. Try Gurobi Try Gurobi. Solves All Major Problem Types. Linear programming LP. Mixed-integer linear programming MILP. Quadratic programming QP.Our code was built to fully exploit parallelism. Our MIP cutting plane routines are second to none. Our advanced MIP heuristics for quickly finding feasible solutions often produce good quality solutions where other solvers fall flat.
Our barrier algorithms fully exploit the features of the latest computer architectures. And our APIs are designed to be lightweight, modern and intuitive, so as to minimize your learning curve while maximizing your productivity.
Please email sales gurobi. Search for: Search. Gurobi Optimizer Technical Features and Details. Unique Features We have added a range of capabilities: A Python API that provides the advantages of both a modeling language and a full programming language. Support for models with multiple, competing objectives and two options to solve them. The ability to directly solve models with piecewise-linear objective functions, to better capture certain non-linear problems. Below is an extensive list of Gurobi's technical features, details and benefits.
Features Detail Benefit for You Outstanding solve times Gurobi has a history of leading public benchmarks and making continual improvements across a range of problem types. Gurobi is tuned to optimize performance over a wide range of instances. You can see the standard public benchmarks, maintained by Hans Mittelmann at Arizona State University.
Add complexity to your model to better represent the real world, and still solve your model within the available time.
Extremely robust code Robustness has several components: numerical stability, correctness of results, scalability with problem size and difficulty, and robustness of solve times over a range of model instances.
Gurobi is tested thoroughly for numerical stability and correctness using an internal library of over 10, models from industry and academia. Have confidence in your results. Flexible licensing Each license can be used for both development and deployment. Each license can run multiple applications. Licenses can be transferred from consulting developer to end user. License grows as chip capabilities grow.
The license fits to your situation. Client-server capabilities Easily build scalable and reliable applications that support multiple simultaneous users across a range of computing platforms Includes job queueing and load-balancing More easily share optimization power and machines for your developers and users.
Cloud computing Provide your own team and end-users with instant access to powerful optimization capabilities on fast machines. Outstanding support Direct access to experienced, PhD-trained optimization experts Support is backed by the Gurobi development team Get answers when you need them — in hours, not days.
For an overview of the different available license types, please visit our licensing overview page. View Licensing.
The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I am using CPLEX for solving huge optimization models more than k variables now I'd like to see if I can find an open source alternative, I solve mixed integer problems MILP and CPLEX works great but it is very expensive if we want to scale so I really need to find an alternative or start writing our own ad-hoc optimization library which will be painful.
I personally found GLPK better i. It supports various file formats, and a further advantage is its library interface, which allows smooth integration with your application. We found that the linear optimiser component Clp was very strong, and the mixed integer component Cbc could be tuned quite well with some analysis. Try the SCIP solver. Gurobi will use multicores to speed up the solver. There were also some other suggestions in the following questions, for Java:.
I recommend checking out the COIN project. Many good solvers here, including ipOPT for nonlinear problems and a couple mixed integer solvers as well. If, on the contrary, the problems are small, then the time for copying the problems from python's memory to the solver back and forth is not to be neglected anymore: in that case you may experiment some noticeable performance improvements using a compiled language.
But if the problems are overwhelmingly enormous, then compiled languages are going to win again, because the memory footprint will be roughly divided by 2 no copy of the problem in python. Although this is maybe not what you want to hear, but there are light-years between the commercial solvers CPLEX and Gurobi on the one hand and open source solvers on the other hand. Nevertheless you can be lucky and your model works fine with GLPK, Coin or the like, but in general open source solutions are way behind the commercial solvers.
If it was different, no one would pay In the past years I have seen many, many models that were just to difficult for the open source solvers. Believe me But what is missing to be really open source is the source code of the solver itself. Many of the open-source libraries do not function well with that many variables.
Using the commercial system may be your only choice. There are certain constraints to submitting jobs to NEOS and it is slightly cumbersome but the free access to a powerful commercial solver more than makes up for it.GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together. If nothing happens, download GitHub Desktop and try again. If nothing happens, download Xcode and try again.
If nothing happens, download the GitHub extension for Visual Studio and try again. It handles creating the model and solving it. It doesn't support loading model from file. Add package to project. Add MilpManager package to project. Skip to content.
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Gurobi Optimizer Technical Features and Details
The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. Apparently, it is not giving what I am looking for.
Since I am using dictionaries everywhere, I want to keep it consistent by continuing to use dictionaries so that I can do multiplications and additions with my parameters which are all in dictionaries. Is there any way to create these variables with m. It looks like you want to create 10 variables that are indexed by something. The best way to do this is to create the two indexes as lists. If you want x, x, then write:. Learn more. Using Gurobi in Python and adding variables Ask Question.
Asked 2 years, 11 months ago. Active 2 years, 11 months ago. Viewed 2k times. Edit: Modified to make it more clear. This should be very simple. Even another Gurobi Optimization beginner can help me with this.
Active Oldest Votes. Greg Glockner Greg Glockner 4, 2 2 gold badges 15 15 silver badges 20 20 bronze badges. Firstly, thanks for your help. I realized that for consistency, I need to use dictionaries rather than tuplelists. Any way to do the same thing for dictionaries like setting il as a dictionary? My purpose is not to type all numbers one by one.
There are more than 10 values in i. I am just trying to understand the logic with the small sample. Nevermind, I got how to do it! Thanks for your comment. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown.
The Overflow Blog. The Overflow How many jobs can be done at home?Purpose Test of an air-crew schedule generation problem. Calling Syntax grbaircrew Description Test of an air-crew schedule generation problem. Based on D. Two subfunctions are used defined at the end of the grbaircrew.
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Tours of Duty. The function sectordata generates some test data. M-files Used abc2gap. The test problem 1 and 2 have variables, 23 equalities and four inequalities with both lower and upper bounds set. Test problem 1, in bilp 1. It has several minima with optimal zero value. Test problem 2, in bilp 2. Runs faster if avoiding the use of presolve. Test problem 3, in bilp Runs very slow without the use of cuts.
A call grbbiptest 0,0 gives the fastest execution for the first two problems, but will be extremely slow for the third problem. Timings are made with the Matlab functions tic and toc. M-files Used gurobi. The test problems have 61 variables and linear inequalities.
The three problems are stored in ilp Code is included to remove the 32 zero rows, and compute better upper bounds using the positivity of the matrix elements, right hand side and the variables.
M-files Used gurobixprintigrbPrint.