The purpose of the application is to provide convenient tools for creating and solving models of objects for linear optimization.
 Linear optimization, also called linear programming (LP), is a method to achieve the best outcome (such as maximum( minimum) profit or lowest cost) in a mathematical model whose requirements and objective are represented by linear relationships. Linear programming is a special case of mathematical programming (also known as mathematical optimization).
Linear programs( models in sense of this app) are problems that can be expressed in  standard formas(Wikipedia):- find vector x; - that maximizes(minimizes) Z = cx; - subject to Ax=b – in minimizes );- and x>=0. Here the components of  x  are the variables to be determined, c and b are given vectors, and A is a given matrix.
From the initial activity of the application – App Linear Optimization, the functions for creating, editing, solving and deleting models are included. The models are stored in SQLite data base with name linearProgramming.db. The application has functions for storing and restoring the database in the directory Download of the device.
When creating an optimization model, two parameters are entered(Linear Model activity) - the number of vector x variables and the number of constraints (this does not include the constraints for variables) – i.e. the rows of the matrix A . After entering these data and pressing the button – Linear Model, you proceed to enter the model data – from activity Linear Model Creation.
The vector x coefficients c are entered in the line with a label Z= in front of the labels *Xi+.
The elements of the matrix А are entered in the table named Constraints in front of the fields label *Xi+. In the last field of each row of the matrix after the label