java - 线程数组 Java 矩阵

Question

我有一个矩阵运算加、减、乘的代码。该代码生成两个矩阵，其中包含用户指定维度内的随机元素。我的问题是我必须为输出矩阵的每个元素创建一个线程。我尝试使用数组来存储线程，但它返回“mul”错误，这是我用于实现 run 的方法的变量。当然，主方法的类中有两个带有 Thread 数组的不同类，下一个类包含我所有的 Matrix 运算算法，还包含为 run 方法实现 Runnable 的类“MatrixThreads”。如果有人可以看一下并看看是否可以帮助我，我将非常感激。

MatrixOperations 类

public class MatrixOperations{
    public static void main(String args[]) throws InterruptedException{
        int row1,col1,row2,col2;

        Scanner sc = new Scanner(System.in);

        System.out.print("\n\n Input Matrix 1 dimensions (ROWS space     COLUMNS):");
        row1= sc.nextInt();
        col1 = sc.nextInt();

        System.out.print("\n\n Input Matrix 2 dimensions (ROWS space COlUMNS):");
        row2= sc.nextInt();
        col2 = sc.nextInt();

        int operation;

        System.out.print("\n\n Select the operation to executed: 1. Add 2. Subtract 3. Multiply \n > ");
        operation = sc.nextInt();

        Matrix result;
        Matrix m1 = new Matrix(row1, col1);
        Matrix m2 = new Matrix(row2, col2);
        int m3 = col1*row2;


        Thread myThreads[]= new Thread[m3];
        for(int i=0; i<m3;i++){
            myThreads[i] = new Thread(new MatrixOperations(mul));//here is the error
            myThreads[i].start();
        }
        for (int i=0; i<m3;i++){
            myThreads[i].join();

        }
        switch(operation){
            case 1:
                result = m1.add(m2);
                System.out.println("\n\n First Matrix: \n " + m1.getPrintableMatrix());
                System.out.println("\n\n Second Matrix: \n " + m2.getPrintableMatrix());
                System.out.println("\n\n Resultant Matrix: \n " + result.getPrintableMatrix());

                break;

            case 2:
                result = m1.subtract(m2);

                System.out.println("\n\n First Matrix: \n " + m1.getPrintableMatrix());
                System.out.println("\n\n Second Matrix: \n " + m2.getPrintableMatrix());
                System.out.println("\n\n Resultant Matrix: \n " + result.getPrintableMatrix());


                break;

            case 3:

                result = m1.dotProduct(m2);

                System.out.println("\n\n First Matrix: \n " + m1.getPrintableMatrix());
                System.out.println("\n\n Second Matrix: \n " + m2.getPrintableMatrix());
                System.out.println("\n\n Resultant Matrix: \n " + result.getPrintableMatrix());

                break;

            default: System.out.println("\nInvalid operation......\n");break;
        }
        System.out.print("\n\n");
    }
}

矩阵类

import java.util.Scanner;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;

public class Matrix {
    private int row,column;
    private double [][] matrixElements;

    class ThreadMatrix implements Runnable{
        private Matrix mul;

        public ThreadMatrix(Matrix mul){
            this.mul = mul;
        }

        @Override
        public void run() {
            mul.add(mul);
        }
    }

    public Matrix (int rows, int columns){
        this.row= rows;
        this.column = columns;
        matrixElements = new double[row][column];
        populatematrix(-100,100);
    }


    public Matrix(double[][] matrixArray){
        this.row = matrixArray.length;
        this.column = (matrixArray[0]).length;
        matrixElements = new double [row][column];
        for (int i=0; i<row;i++){
            for (int j=0; j<column;j++){
                matrixElements[i][j] = matrixArray[i][j];
            }
        }
    }

    private void populatematrix(int min, int max){
        Random randnum = new Random();
        Random rand = new Random();

        for (int i=0; i<row; i++){
            for (int j= 0;j<row;j++){
                matrixElements[i][j] = rand.nextInt((max - min) + 1) + min;
            }
        }
    }
    public Matrix add(Matrix otherMatrix){
        double[][] resultMatrixArray = new double[this.row][this.column];
        for (int i=0; i<row; i++){
            for (int j=0; j<column; j++){
                resultMatrixArray[i][j] = this.matrixElements[i][j] + otherMatrix.matrixElements[i][j];

            }

        }
        return new Matrix(resultMatrixArray);
    }

    public Matrix subtract(Matrix otherMatrix){
        double[][] resultMatrixArray = new double[row][column];

        for (int i=0; i<row; i++){
            for (int j=0; j<column; j++){
                resultMatrixArray[i][j] = this.matrixElements[i][j] - otherMatrix.matrixElements[i][j];
            }
        }
        return new Matrix(resultMatrixArray);

    }

    public Matrix dotProduct(Matrix otherMatrix){

        double[][] resultMatrixArray = new double [row][column];

        double sum = 0;

        if (this.column !=otherMatrix.row)
            System.out.println("\n\n Matrices Multiplication is not possible...Invalid Dimensions...\n\n");
        else {
            for (int c=0; c<this.row;c++){
                for (int d = 0; d<otherMatrix.column;d++){
                    for (int k = 0; k<otherMatrix.row; k++){
                        sum = sum+((this.matrixElements[c][k])*(otherMatrix.matrixElements[k][d]));
                    }
                    resultMatrixArray[c][d]=sum;
                    sum = 0;
                }
            }
        }
        return new Matrix(resultMatrixArray);
    }

    public String getPrintableMatrix(){
        String result ="";

        for (double[] roww: matrixElements){
            for (double j:roww){
                result +=""+j + "";
            }
            result +="\n";
        }
        return result;
    }
}

Answer 1

首先，你的问题非常不清楚；但我想我可以给出足够的答案来让你继续下去。也许你可以澄清一下；我们从那里看得更远。所以...

不清楚:“每个输出一个线程”矩阵是什么意思。这样做根本没有意义。也许您想在多个矩阵上并行运行不同操作；您应该为此使用线程。

现在，为了帮助您:您的模型过于简单使您的整个设计变得过于复杂，以至于解决您的问题看起来比应有的复杂得多。

我的意思是:你混淆了职责:你看，矩阵应该是关于矩阵数据的；也许还有关于可以应用于矩阵的数学运算。因此:将整个“线程业务”排除在外。编写允许您创建两个矩阵的代码；然后对其运行 add()、multiple() 等操作。

然后，当一切顺利时； 实例化这些 Matrix 对象的代码，该代码可以使用多个线程并行执行 A+B、A*C、A-D 等操作。