llgptab {goalprog}R Documentation

Create lexicographical LGP tableau

Description

This function returns the initial modified simplex tableau as an object of type 'llgptab' for a lexicographical linear programming problem for the given objectives and achievement goals

Usage

llgptab(coefficients, targets, achievements)

Arguments

coefficients A matrix with the coefficients of the linear objective functions
targets A vector of target values for the objective functions
achievements A data frame with the weights of the deviation variables for each objective along with the corresponding priority level

Details

The modified simplex tableau contains a top stub matrix, a left stub matrix, an elements matrix, index rows and achievement vector as specified in Ignizio (1976).

Value

An object of class 'llgptab' which is a list with the following named components

iter Current iteration number initially set to zero
variables Number of decision variables
levels Number of priority levels in the achievement function
objectives Number of objective functions
nonbasics Number of non basic variables = variables + objectives
level Current priority level
te Elements matrix
tb Vector b initially the target values
tw Top stub matrix
tu Left stub matrix
ti Matrix of index rows
ta Achievement vector
row.headings Vector of row headings initially the negative deviation variables
col.headings Vector of column headings initially the decision and positive deviation variables

Author(s)

Frederick Novomestky fnovomes@poly.edu

References

Ignizio, J. P. (1976). Goal Programming and Extensions, Lexington Books, D. C. Heath and Company.

Examples

data( ignizio.example.3.3 )
tab <- llgptab( coefficients, targets, achievements )

[Package goalprog version 1.0-2 Index]