# llgp: Solve an LLGP problem In goalprog: Weighted and lexicographical goal programming and optimization

## Description

Solve a lexicographical linear goal programming (LLGP) problem using a modified primal simplex algorithm.

## Usage

 `1` ```llgp(coefficients, targets, achievements, maxiter = 1000, verbose = FALSE) ```

## Arguments

 `coefficients` A matrix of coefficients for the linear objective functions `targets` A vector of target values for the objective functions `achievements` A data frame with the deviation variables for each objective together with the priority level `maxiter` The maximum number of interations with a default value of 1000 `verbose` A logical value that determines if intermediate tableaus are to be printed

## Details

The function implements the Ignizio (1976) modified simplex algorithm. When the user selects verbose=TRUE, the modified simplex tableau is printed at each iteration.

## Value

An object of class 'llgp' which is a list with three named components

 `tab ` An object of type 'llgptab' for the modified simplex tableau `solution ` An object of typel 'llgpout' for the optimal solution `converged ` A logical value that determines if the algorithm converged to the optimal solution

## Author(s)

Frederick Novomestky fnovomes@poly.edu

## References

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

`check.tb`, `calc.ti.k`, `calc.ta.k`, `ev.llgp`, `dv.llgp`, `piv.llgp`, `llgptab`, `llgpout`

## Examples

 ```1 2``` ```data( ignizio.example.3.3 ) soln <- llgp( coefficients, targets, achievements ) ```

### Example output

```Loading required package: lpSolve
```

goalprog documentation built on May 30, 2017, 5:07 a.m.