以列方式从二进制矩阵获得1的索引

时间:2018-06-08 23:09:20

标签: c matrix binary sparse-matrix indices

1 1 0 1 0 0
0 1 1 0 1 0
1 0 0 0 1 1
0 0 1 1 0 1

我实现了一个程序,以列方式查找1的索引。例如,以上面的二进制矩阵为例,应该获得的索引是: 0 2 0 1 1 3 0 3 1 2 2 3.

我的问题是,要获得这些索引,我必须添加两个额外的行,其中包含零。我实施的完整工作计划如下:

#include <stdio.h>
#include <stdlib.h>
#define padding 2
#define rows_Matrix 4  + padding
#define cols_Matrix 6

int main() 
{

   int index = 0;

   //Allocation of Memory for the Binary Matrix. 
   unsigned **Matrix = (unsigned**)malloc(sizeof(unsigned*)*rows_Matrix); //Rows

   for (int i = 0; i < rows_Matrix; i++) //Rows
   {
       Matrix[i] = (unsigned *)malloc(sizeof(unsigned) * cols_Matrix); //Columns 
   }

   //Assigning elements to the Binary Matrix. 
   Matrix[0][0] = 1; Matrix[0][1] = 1; Matrix[0][2] = 0; Matrix[0][3] = 1;  Matrix[0][4] = 0;  Matrix[0][5] = 0;
   Matrix[1][0] = 0; Matrix[1][1] = 1; Matrix[1][2] = 1; Matrix[1][3] = 0;  Matrix[1][4] = 1;  Matrix[1][5] = 0;
   Matrix[2][0] = 1; Matrix[2][1] = 0; Matrix[2][2] = 0; Matrix[2][3] = 0;  Matrix[2][4] = 1;  Matrix[2][5] = 1;
   Matrix[3][0] = 0; Matrix[3][1] = 0; Matrix[3][2] = 1; Matrix[3][3] = 1; Matrix[3][4] = 0;  Matrix[3][5] = 1;

   //Added padded rows of 0s to get the Matrix a square in order to obtain indices.
   Matrix[4][0] = 0; Matrix[4][1] = 0; Matrix[4][2] = 0; Matrix[4][3] = 0;  Matrix[4][4] = 0;  Matrix[4][5] = 0;
   Matrix[5][0] = 0; Matrix[5][1] = 0; Matrix[5][2] = 0; Matrix[5][3] = 0;  Matrix[5][4] = 0;  Matrix[5][5] = 0;

   //Finding indices of number of 1s in the columns of the matrix.
   printf("Vertical Indices of 1s in the Matrix:\n");

   for (int i = 0; i < rows_Matrix; i++)
   {
      for (int j = 0; j < cols_Matrix; j++)
      {
         if (Matrix[j][i] == 1)
         {
            index = j;
            //Printing indices of 1s in a column fashion.
            printf("%d\t", index); 
         }
      }
   }
   printf("\n");

  return 0;
}

我实施的计划的输出如下:

矩阵中1s的垂直指数: 0 2 0 1 1 3 0 3 1 2 2 3

我想将矩阵保留为4x6矩阵而不是6x6矩阵,并且仍然可以获得我在程序中获得的上述索引。有没有办法获得这些索引而无需在C中添加额外的填充?

2 个答案:

答案 0 :(得分:0)

我认为你的问题在这里:

for (int i = 0; i < rows_Matrix; i++)
{
   for (int j = 0; j < cols_Matrix; j++)

您需要交换行和列,如:

for (int i = 0; i < cols_Matrix; i++)  // cols instead of rows
{
   for (int j = 0; j < rows_Matrix; j++)  // rows instead of cols

执行此操作后,您可以删除填充

答案 1 :(得分:0)

预处理器定义

#define rows_Matrix 4  + padding

应该是

#define rows_Matrix (4  + padding)

如果你看这一行

unsigned **Matrix = (unsigned**)malloc(sizeof(unsigned*)*rows_Matrix);

它扩展到

unsigned **Matrix = (unsigned**)malloc(sizeof(unsigned*)*4  + padding);

这在

中的表现不一样
for (int i = 0; i < rows_Matrix; i++)

错误是良性的。 始终将括号放在预处理程序语句周围。