MatrixMultiplyMatrixMatrix.java

package info.kalendra.matrixOps;

import info.kalendra.matrix.Matrix;

import java.security.InvalidParameterException;

public class MatrixMultiplyMatrixMatrix {

	public Matrix multiply(Matrix x, Matrix y, Matrix z){
		//check dimensions
		if(x.getDimensionCols() != y.getDimensionRows()){
			throw new InvalidParameterException("Dimensions don't match");
		}
		//set the dimensions of z
		z.setDimensions(x.getDimensionRows(), y.getDimensionCols());
		//push the data into z
		double temp1;
		double temp2;
		for(int i = 0; i < x.getDimensionRows(); i++){
			for(int j =0; j < y.getDimensionCols(); j++){
				for(int k = 0; k < x.getDimensionCols(); k++){
					temp1 = z.getValue(i, j);
					temp2 = x.getValue(i, k) * y.getValue(k, j);
					z.setValue(i, j, temp1 + temp2);
				}
			}
		}
		return z;
	}
}