- la4j-0.2.0.zip
- la4j
- bin
- la4j-0.2.0.jar
- LICENSE
- README
- src
- main
- java
- la4j
- decomposition
- err
- factory
- inversion
- io
- linear
- matrix
- util
- vector
- test
- java
- la4j
- decomposition
- inversion
- linear
- matrix
- vector
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/*
* Copyright 2011, Vladimir Kostyukov
*
* This file is part of la4j project (http://la4j.googlecode.com)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* You may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package la4j.linear;
import la4j.err.LinearSystemException;
import la4j.factory.Factory;
import la4j.matrix.Matrix;
import la4j.vector.Vector;
public class ZeidelSolver implements LinearSystemSolver {
private final static int MAX_ITERATIONS = 100000;
@Override
public Vector solve(LinearSystem linearSystem, Factory factory) throws LinearSystemException {
Matrix a = linearSystem.coefficientsMatrix().clone();
Vector b = linearSystem.rightHandVector();
if (!isMethodCanBeUsed(a)) throw new LinearSystemException("Zeidel method can not be used");
for (int i = 0; i < a.rows(); i++) {
for (int j = 0; j < a.columns(); j++) {
if (i != j) a.set(i, j, a.get(i, j) / a.get(i, i));
}
}
Vector current = factory.createVector(linearSystem.variables());
int iteration = 0;
while (iteration < MAX_ITERATIONS && !linearSystem.isSolution(current)) {
for (int i = 0; i < a.rows(); i++) {
double summand = b.get(i) / a.get(i, i);
for (int j = 0; j < a.columns(); j++) {
if (i != j) summand -= a.get(i, j) * current.get(j);
}
current.set(i, summand);
}
iteration++;
}
if (iteration == MAX_ITERATIONS) throw new LinearSystemException("method Zeidel can not be used");
return current;
}
private boolean isMethodCanBeUsed(Matrix matrix) {
for (int i = 0; i < matrix.rows(); i++) {
double sum = 0;
for (int j = 0; j < matrix.columns(); j++) {
if (i != j) sum += Math.abs(matrix.get(i, j));
}
if (sum > Math.abs(matrix.get(i, i)) - EPS) return false;
}
return true;
}
}
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I've received a Master's Degree in Computer Science at the IT Faculty of Altai State Technical University, Russia.
Currently, I am Software Engineer at Intel Corporation.