/*
GeoGebra - Dynamic Mathematics for Everyone
http://www.geogebra.org
This file is part of GeoGebra.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation.
*/
package org.geogebra.common.kernel.algos;
import org.geogebra.common.kernel.Construction;
import org.geogebra.common.kernel.commands.Commands;
import org.geogebra.common.kernel.geos.GeoElement;
import org.geogebra.common.kernel.geos.GeoList;
import org.geogebra.common.kernel.geos.GeoNumeric;
/**
* Product of square matrices {A,B,C} returns A*B*C
*
* @author Michael Borcherds
*/
public class AlgoProductMatrices extends AlgoElement {
private GeoList geoList; // input
private GeoList result; // output
@SuppressWarnings("javadoc")
public AlgoProductMatrices(Construction cons, String label,
GeoList geoList) {
super(cons);
this.geoList = geoList;
// make sure output is same type as input (GeoVector, GeoPoint,
// GeoPoint3D)
result = new GeoList(cons);
setInputOutput();
compute();
result.setLabel(label);
}
@Override
public Commands getClassName() {
return Commands.Product;
}
@Override
protected void setInputOutput() {
input = new GeoElement[1];
input[0] = geoList;
super.setOutputLength(1);
super.setOutput(0, result);
setDependencies(); // done by AlgoElement
}
@SuppressWarnings("javadoc")
public GeoElement getResult() {
return result;
}
@Override
public final void compute() {
int size = geoList.size();
if (!geoList.isDefined() || size == 0 || !geoList.get(0).isMatrix()) {
result.setUndefined();
return;
}
GeoList matrix = (GeoList) geoList.get(0);
if (size == 1) {
result.set(matrix);
return;
}
double working[][] = new double[matrix.size()][matrix.size()];
double working2[][] = new double[matrix.size()][matrix.size()];
// fill initial matrix
for (int r = 0; r < matrix.size(); r++) {
for (int c = 0; c < matrix.size(); c++) {
working2[r][c] = matrix.get(r, c).evaluateDouble();
// Log.debug(working2[r][c]);
}
}
for (int i = 1; i < size; i++) {
GeoElement p = geoList.get(i);
if (!p.isMatrix()) {
result.setUndefined();
return;
}
matrix = (GeoList) p;
// check matrix is square
if (((GeoList) matrix.get(0)).size() != matrix.size()) {
result.setUndefined();
return;
}
// fill working matrix
for (int r = 0; r < matrix.size(); r++) {
for (int c = 0; c < matrix.size(); c++) {
working[r][c] = working2[r][c];
// Log.debug(working2[r][c]);
}
}
// do the multiplication for one matrix
for (int r = 0; r < matrix.size(); r++) {
for (int c = 0; c < matrix.size(); c++) {
double count = 0;
// Log.debug(" ");
for (int n = 0; n < matrix.size(); n++) {
count += working[r][n]
* matrix.get(n, c).evaluateDouble();
// Log.debug(working[r][n] +" * "+ matrix.get(n,
// c).evaluateDouble());
}
working2[r][c] = count;
}
}
}
// put result back in a GeoList
GeoList ret = new GeoList(cons);
for (int r = 0; r < matrix.size(); r++) {
GeoList row = new GeoList(cons);
for (int c = 0; c < matrix.size(); c++) {
row.add(new GeoNumeric(cons, working2[r][c]));
}
ret.add(row);
}
result.set(ret);
}
}