跪求一个距阵相乘的程序!!!

我写的矩阵类，供参考：public class Matrix {
private int[] data;
private int rows, cols;
public Matrix(int rows, int cols) {
this.rows = rows;
this.cols = cols;
data = new int[rows * cols];
}
public Matrix(int rows, int cols, int[] src) {
this(rows, cols);
System.arraycopy(src, 0, data, 0, Math.min(src.length, data.length));
}
public Matrix multiply(Matrix multiplyer) {
if (cols != multiplyer.rows) throw new RuntimeException("Cannot multiply these 2 matrixes."); Matrix product = new Matrix(rows, multiplyer.cols);
for (int i = 0; i < product.rows; i++) {
for (int j = 0; j < product.cols; j++)
for (int k = 0; k < cols; k++)
product.data[i*product.cols+j] += data[i*cols+k] * multiplyer.data[k*multiplyer.cols+j];
}
return product;
}
public String toString() {
StringBuffer buf = new StringBuffer();
for (int i = 0; i < data.length; i++) {
if (i % cols == 0) buf.append("|");
buf.append(" " + data[i]);
if ((i+1) % cols == 0) buf.append(" |\n");
}
return buf.toString();
}
}包含一个multiply方法，未使用二维数组，而是使用一维数组存储的，因为JAVA的二维数组是锯齿状的，不适合做矩阵乘法。元素默认初始化为0。用法举例：Matrix m1 = new Matrix(2, 2, new int[] { 1, 3, 4, 10 });
Matrix m2 = new Matrix(2, 3, new int[] { 4, 1, 5, 8 });
System.out.println(m1);
System.out.println(m2);
System.out.println(m1.multiply(m2));输出：| 1 3 |
| 4 10 || 4 1 5 |
| 8 0 0 || 28 1 5 |
| 96 4 20 |
有时间的话，把加法，减法，数乘补上，呵呵。
import java.text.DecimalFormat;
public class MatrixProduct implements Cloneable, java.io.Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
private double[][] A;
private int m, n;
public MatrixProduct (int m, int n) {
      this.m = m;
      this.n = n;
      A = new double[m][n];
   }
   public MatrixProduct (double[][] A) {
      m = A.length;
      n = A[0].length;
      for (int i = 0; i < m; i++) {
         if (A[i].length != n) {
            throw new IllegalArgumentException("All rows must have the same length.");
         }
      }
      this.A = A;
   }    public MatrixProduct (double[][] A, int m, int n) {
      this.A = A;
      this.m = m;
      this.n = n;
   }    public MatrixProduct (double vals[], int m) {
      this.m = m;
      n = (m != 0 ? vals.length/m : 0);
      if (m*n != vals.length) {
         throw new IllegalArgumentException("Array length must be a multiple of m.");
      }
      A = new double[m][n];
      for (int i = 0; i < m; i++) {
         for (int j = 0; j < n; j++) {
            A[i][j] = vals[i+j*m];
         }
      }
   }
   public double[][] getArray () {
      return A;
   }
   public MatrixProduct product (MatrixProduct matrix) {
      if (matrix.m != n) {
         throw new IllegalArgumentException("Matrix inner dimensions must agree.");
      }
      MatrixProduct M = new MatrixProduct(m,matrix.n);
      double[][] C = M.getArray();
      double[] B_kol = new double[n];
      for (int j = 0; j < matrix.n; j++) {
         for (int k = 0; k < n; k++) {
            B_kol[k] = matrix.A[k][j];
         }
         for (int i = 0; i < m; i++) {
            double[] Arowi = A[i];
            double s = 0;
            for (int k = 0; k < n; k++) {
               s += Arowi[k]*B_kol[k];
            }
            C[i][j] = s;
         }
      }
      return M;
} public void print (int w, int d) {
   DecimalFormat format = new DecimalFormat();
   int width=0;
   //System.out.print(false);  // start on new line.
      for (int i = 0; i < m; i++) {
         for (int j = 0; j < n; j++) {
            String s = format.format(A[i][j]); // format the number
            int padding = Math.max(1,width-s.length()); // At _least_ 1 space
            for (int k = 0; k < padding; k++)
             System.out.print(' ');
            System.out.print(s);
         }
         System.out.print("\n");
      }
      System.out.print("\n");
      }}
public class ProductMatrix { /**
* @param args
*/
public static void main(String[] args) {
double[][] vals = {{1.,2.,3},{4.,5.,6.},{7.,8.,10.}};
double[][] vals_1 = {{5,4,6,7},{3,2,4,3},{5,8,2,2}};
      MatrixProduct A = new MatrixProduct(vals);
      MatrixProduct B = new MatrixProduct(vals_1);
      MatrixProduct C=A.product(B);
      C.print(0,2); }}二维数组写的(顺便问一句,LZ为什么不用API,API里几乎所有的运算都包含了,你不用.)
:)

调试易

跪求一个距阵相乘的程序!!!

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