What'sBest, LINGO and LINDO API all utilize the same set of underlying solvers and can solve the same types of problems. They primarily differ in terms of how models are expressed and how you interface with them.
What'sBest is an add-on to Microsoft Excel. Models can be expressed in a free form fashion in an Excel file using standard spreadsheet equations. Whatâ€™sBest may be the easiest product to learn and begin using for users comfortable using Excel.
With LINGO the user can utilize a modeling language to express the model. The modeling language supports summations and subscripted variables to allow you to express large models quickly. LINGO can also read data from and write solution information to Excel and Windows databases such as Microsoft Access. LINGO includes a user interface for interactive use and a callable programming interface that allows you to embed LINGO in your own application.
LINDO API does not have a traditional user interface. It only has a programming interface. Of the three products, it gives the application developer the most control over the optimization process and can allow the user to tailor the algorithm to a particular model or even develop a new algorithm.
For more information on each of the products you can visit our Product page and to download trial versions of each product see our Download page.
The Base versions of each product include Primal and Dual Simplex algorithms for linear models and includes integer programming capabilities. We offer a few different options that extend the capabilities of the base versions. Whether or not you need an option depends upon the types of models that you wish to solve. If your models are linear (with or without integer restrictions) no options are required.
The Barrier option adds a Barrier/Interior Point solver. If you have a quadratic model (i.e., an model with a quadratic objective function and/or quadratic constraints with all other terms being linear) then the Barrier option will provide the best performance. Quadratic models can be solved with the general Nonlinear solver but it will generally take longer. The Barrier option can also be used to solve linear models with no integer restrictions. In some cases using the Barrier algorithm may be significantly faster that using the Primal and Dual Simplex algorithms available in the base versions. This is typically true on sparse models with more than 5,000 constraints or highly degenerate models.
The Nonlinear option can allow you to solve general nonlinear models to a local optimum using a Generalized Reduced Gradient (GRG) algorithm. If your models are nonlinear and convex (i.e., only one local optimum) then you can use the Nonlinear option to solve your models. However, many classes of nonlinear models are non-convex (i.e., have more than one local optimum). Using the Nonlinear option alone, the solver will stop at the first locally optimal solution it finds. Other local optimum may exist that are significantly better than the local optimum returned. For nonconvex models you may want to use the Nonlinear option in conjunction with the Global option.
The Global option provides two additional techniques for solving nonlinear models â€“ a Global solver and a Multistart capability. Rather than stopping after the first local optimum is found, the Global solver will search until the global optimum is confirmed. When limited time makes searching for the global optimum prohibitive, the Multistart capability can be a powerful tool for finding good solutions more quickly. This capability intelligently selects different starting points and solves each to a local optimum and then returns the best solution found. For non-convex nonlinear models, the quality of the solution returned using the Multistart capability will be superior to that of the general nonlinear solver. The Global option requires the Nonlinear option.
Other than capacity, there are no differences in the performance, features or functionality of the different sized versions.
We try to make it easy for you to upgrade your capacity if necessary. If you decide to upgrade to a larger version of the same product within 60 days of your purchase, then you would simply pay the difference in price. After 60 days, you would pay the difference plus $25.
Yes, if you order from our website www.lindo.com/store you will be able to select Electronic from the different shipping options.
We will then email you a license key along with download instructions.
All LINDO Systems software comes with a 60 day satisfaction guarantee. You are free to use the 60 day period as a trial period. This allows you to set up and solve a few problems, become familiar with the software and all of its features, and make certain that you have made the right choice. If, for any reason, you are not completely satisfied with the product you may exchange it for another product or return it within 60 days for a full refund.
Our development team is always working on the next release of the software. If you purchase a license and we issue a new release within 60 days of your purchase you are entitled to a download update of the new release at no charge. After 60 days, the standard update fee is generally 20% of the standard license price.
You can create and distribute turnkey optimization applications that utilize our products. Each user of the application would need at least a runtime license for our product. Runtime licenses are sold at discount off the standard license price, and we require application developers to sign a runtime license agreement. Contact us for details.
If you place an order for several single user licenses of a particular product we offer quantity discounts*. On orders for 2 to 5 licenses you would get 20% off the standard price, on 6 to 10 you would get 30% off, and on 11 or more you would get 40% off.
*Note : We do not offer these discounts for the Educational Solver Suite licenses.
We offer commercial and educational site licenses. Commercial site licenses are negotiated on a case by case basis. A commercial site license is generally only economical if you have more than about 20 users. Otherwise it is more appropriate to buy single user licenses and install them locally.
For a price quote on a commercial site license contact us with information on the site to be covered (e.g., whether it covers a department, single physical, an entire company, etc.) and an estimate of the number of users. Also, let us know the product, capacity and options you require.
We also offer educational site licenses to cover a particular department, lab or network. Contact us for pricing.