AMPL R API

rAMPL is an interface that allows developers to access the features of AMPL from within R. For a quick introduction to AMPL see Quick Introduction to AMPL.

In the same way that AMPL’s syntax matches naturally the mathematical description of the model, the input and output data matches naturally R data types such as vectors and dataframes.

All model generation and solver interaction is handled directly by AMPL, which leads to great stability and speed; the library just acts as an intermediary, and the added overhead (in terms of memory and CPU usage) depends mostly on how much data is sent and read back from AMPL, the size of the expanded model as such is irrelevant.

With rAMPL you can model and solve large scale optimization problems in R with the performance of heavily optimized C code without losing model readability. The same model can be deployed on applications built on different languages by just switching the API used.

Contents

• Introduction
  • What are AMPL APIs?
  • Who can use AMPL APIs
  • System requirements
  • About this manual
• Initial Setup
  • Installation
  • Initial test
  • Development
  • Deployment
• Quick Start
  • Complete listing
  • Needed headers and AMPL environment creation
  • Load a model from file
  • Solve a problem
  • Get an AMPL entity in the programming environment (get objective value)
  • Modify model data (assign values to parameters)
  • Get numeric values from variables
  • Get arbitrary values via ampl expressions
  • Delete the AMPL object to free the resources
• Class structure
  • AMPL class
  • Modelling entities classes
  • Relation between entities and data
  • Note on variables suffixes
• API Reference
  • AMPL classes
  • Algebraic entities classes
• Examples
  • Example 1: First steps
  • Example 2: Get and set AMPL options
  • Example 3: Operate with multidimensional data
  • Example 4: Assign all data to a model and solve it
  • Example 5: Build an efficient frontier
  • Example 6: Simple heuristic