为什么应该将矩阵输出为n的幂的C程序将矩阵输出为2 ^ n的幂?

时间:2018-10-14 12:17:37

标签: c linux unix matrix matrix-multiplication

我的代码应该采用矩阵M并将其提高为整数A的幂。但是,无论如何,我的输出始终为M ^(2 ^ A)。例如,如果我想以3阶幂找到矩阵,则改为获得8阶幂。

#include <stdio.h> 
#include <stdlib.h> 
#include <math.h>
  void multiply(int ** p, int pwr, int dim, int ** prod) {
    int m, i, j, k;
    /*if (n<pwr){*/
    int pos = 0;
    for (m = 0; m < pwr; m++) {
      for (i = 0; i < dim; i++) {
        for (j = 0; j < dim; j++) {
          for (k = 0; k < dim; k++) {
            pos += p[i][k] * p[k][j];
          }
          prod[i][j] = pos;
          pos = 0;
        }
      }
      for (i = 0; i < dim; i++) {
        for (j = 0; j < dim; j++) {
          p[i][j] = prod[i][j];
          prod[i][j] = 0;
        }
      }
    }
    /*n=n+1;
    multiply(prod, q, pwr, dim, prod);
    }*/
  }
int main(int argc, char * argv[]) {
  FILE * fp = fopen(argv[1], "r");
  int dim, pwr, i, j;
  fscanf(fp, "%d", & dim);
  int ** matrix;
  matrix = (int ** ) malloc(dim * sizeof(int * ));
  for (i = 0; i < dim; i++) {
    matrix[i] = (int * ) malloc(dim * sizeof(int));
  }
  int ** prod;
  prod = (int ** ) malloc(dim * sizeof(int * ));
  for (i = 0; i < dim; i++) {
    prod[i] = (int * ) malloc(dim * sizeof(int));
  }
  for (i = 0; i < dim; i++) {
    for (j = 0; j < dim; j++) {
      fscanf(fp, "%d", & matrix[i][j]);
    }
  }
  fscanf(fp, "%d", & pwr);
  if (pwr == 1) {
    for (i = 0; i < dim; i++) {
      for (j = 0; j < dim; j++) {
        printf("%d ", matrix[i][j]);
      }
      printf("\n");
    }
  } else if (pwr >= 2) {
    multiply(matrix, pwr, dim, prod);
    for (i = 0; i < dim; i++) {
      for (j = 0; j < dim; j++) {
        printf("%d ", matrix[i][j]);
      }
      printf("\n");
    }
  }
  return 0;
}

1 个答案:

答案 0 :(得分:1)

您要自己乘以矩阵,然后将结果存储到原始矩阵中。然后您再做一次。

非常正常,它可以通电8次。您需要的是另一个临时矩阵,您可以在上面存储结果,并保留原始矩阵以与结果相乘。