Class GaussianElimination
 Object

 edu.princeton.cs.algs4.GaussianElimination

public class GaussianElimination extends Object
TheGaussianElimination
data type provides methods to solve a linear system of equations Ax = b, where A is an mbyn matrix and b is a length n vector.This is a barebones implementation that uses Gaussian elimination with partial pivoting. See GaussianEliminationLite.java for a strippeddown version that assumes the matrix A is square and nonsingular. See
GaussJordanElimination
for an alternate implementation that uses GaussJordan elimination. For an industrialstrength numerical linear algebra library, see JAMA.This computes correct results if all arithmetic performed is without floatingpoint rounding error or arithmetic overflow. In practice, there will be floatingpoint rounding error; partial pivoting helps prevent accumulated floatingpoint rounding errors from growing out of control (though it does not provide any guarantees).
For additional documentation, see Section 9.9 Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.
 Author:
 Robert Sedgewick, Kevin Wayne


Constructor Summary
Constructors Constructor Description GaussianElimination(double[][] A, double[] b)
Solves the linear system of equations Ax = b, where A is an mbyn matrix and b is a length m vector.

Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description boolean
isFeasible()
Returns true if there exists a solution to the linear system of equations Ax = b.static void
main(String[] args)
Unit tests theGaussianElimination
data type.double[]
primal()
Returns a solution to the linear system of equations Ax = b.



Constructor Detail

GaussianElimination
public GaussianElimination(double[][] A, double[] b)
Solves the linear system of equations Ax = b, where A is an mbyn matrix and b is a length m vector. Parameters:
A
 the mbyn constraint matrixb
 the length m righthandside vector Throws:
IllegalArgumentException
 if the dimensions disagree, i.e., the length ofb
does not equalm


Method Detail

primal
public double[] primal()
Returns a solution to the linear system of equations Ax = b. Returns:
 a solution x to the linear system of equations
Ax = b;
null
if no such solution

isFeasible
public boolean isFeasible()
Returns true if there exists a solution to the linear system of equations Ax = b. Returns:
true
if there exists a solution to the linear system of equations Ax = b;false
otherwise

main
public static void main(String[] args)
Unit tests theGaussianElimination
data type. Parameters:
args
 the commandline arguments

