fmel-method {rPorta}R Documentation

Method "fmel"

Description

Projection of linear system on subspaces xi = 0.

Usage

## S4 method for signature 'ieqFile': 
fmel(object,chernikov_rule_off=FALSE,long_arithmetic=FALSE)

Arguments

object Object of class ieqFile
chernikov_rule_off Fourier-Motzkin elimination without using the rule of Chernikov
long_arithmetic Use long integers for intermediate results.

Details

fmel takes a system of linear inequalities as input and eliminates choosen variables. That is, fmel projects the given system to the subspace given by xi = 0, for i is contained in I, where I is the index set of the variables that should be eliminated.

The set I and the elimination order are given in the input object in the slot elimination_order, containing exactly dim integers, where dim is the dimension of the problem.

A '0' as the i-th entry of elimination_order indicates that the i-th variable should not be eliminated, that is, i is not in I. An entry 'j', for 0 < j < dim, as the i-th entry of elimination_order indicates that the i-th variable should be eliminated in the j-th iteration. (All nonzero numbers must be different and it must be possible to put them into an order 1,2,3,4...)

Value

Returns the resulting inequalities as an ieqFile object.

Author(s)

Robin Nunkesser Robin.Nunkesser@tu-dortmund.de

See Also

"ieqFile"

Examples

# Fourier-Motzkin elimination of an ieqFile
fmel(example.ieq())

[Package rPorta version 0.1-9 Index]