《AMPL编程1.ppt

AMPL编程 主讲人： 贾海成 Introduction AMPL: A Modeling Language for Mathematical Programming Website: Introduction 解决最优化问题模型的计算机软件 (30多种) Introduction 解决最优化问题模型的计算机软件 Introduction Introduction Introduction 什么是最优化问题？ 所谓最优化问题一般是指按照给定的标准在某些约束条件下选取最优的解集。 主要分支： 线性规划、整数规划、二次规划、非线性规划、随机规划、动态规划、组合最优化、无限维最优化 Introduction A simple two-variable linear program A Steel company two products: Bands and Coils production rate (Tons per hour): Bands 200; Coils 140. Profit margin (Profit per ton): Bands $25; Coils $30. Introduction The following weekly production amounts are the most that can be justified in light of the currently booked orders: Maximum tons: Bands 6000; Coils 4000 If 40 hours of production time are available this week, how many tons of bands and how many tons of coils should be produced to bring in the greatest total profit? Introduction Mathematic model Introduction Method 1 Introduction Method 2 Introduction Method 2 Introduction Method 2 Introduction The two-variable linear program in AMPL Prod0.mod prod0.run Introduction Adding one variable A Steel company Three products: Bands, Coils and Plate Production rate (Tons per hour): Bands 200; Coils 140; Plate 160. Profit margin (Profit per ton): Bands $25; Coils $30; Plate $29. Introduction The following weekly production amounts are the most that can be justified in light of the currently booked orders: Maximum tons: Bands 6000; Coils 4000; Plate 3500 If 40 hours of production time are available this week, how many tons of bands and how many tons of coils should be produced to bring in the greatest total profit? Introduction Mathematic model Introduction var XB; var XC; var xp; maximize Profit: 25*XB+30*XC+29*xp; subject to Time: (1/200)*XB+(1/140)*XC+(1/160)*xp=40; subject to B_limit: 0=XB=6000; subject to C_limit: 0=XC=4000; subject to p_limit: