Matrixpublic class Matrix extends Object | Multiply two matrices.
Only defined for int: TODO: rewrite using 1.5 Generics to add
support for long, float, and double. |
| Methods Summary |
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| public static void | mprint(int[][] a)Matrix print.
int rows = a.length;
int cols = a[0].length;
System.out.println("array["+rows+"]["+cols+"] = {");
for (int i=0; i<rows; i++) {
System.out.print("{");
for (int j=0; j<cols; j++)
System.out.print(" " + a[i][j] + ",");
System.out.println("},");
}
System.out.println(":;");
| | public static int[][] | multiply(int[][] m1, int[][] m2)
int m1rows = m1.length;
int m1cols = m1[0].length;
int m2rows = m2.length;
int m2cols = m2[0].length;
if (m1cols != m2rows)
throw new IllegalArgumentException("matrices don't match: " + m1cols + " != " + m2rows);
int[][] result = new int[m1rows][m2cols];
// multiply
for (int i=0; i<m1rows; i++)
for (int j=0; j<m2cols; j++)
for (int k=0; k<m1cols; k++)
result[i][j] += m1[i][k] * m2[k][j];
return result;
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