在C中转置非正方矩阵

Question

everyone I am trying to work on the transpose matrix here is my code so far.

    void Transpose(int mt[][10], int m, int n)
{
  int c,d,temp;
  for (c = 0; c < m; c++)
    {
      for (d = c+1; d < n; d++)
        {
          temp = mt[c][d];
          mt[c][d]=mt[d][c];
          mt[d][c] = temp;
        }
    }
}
void print(int pose[][10], int m, int o)
{
  int i,j;
  for(i = 0; i < m; i++)
    {
      for(j = 0; j < o; j++)
        {
          printf("%d\n",pose[j][i]);
        }
    }
}
int main()
{
  /*The body of your source code will go here */
  int a[4][5] = {{1,2,3,4,5},{6,7,8,9,10},{10,9,8,7,6},{5,4,3,2,1}};
  printf("ARRAY: %d",a[][5]);
  Transpose();                                                               
  return (0);
}

Here is my function for print and transpose a matrix, but now I am trying to pass the array into the function from my main. I just wondering how I declare the array that in the main can pass to the function. Thanks

Answer 1

Your declaration of Transpose does not match your use of it. Since it is declared as:

void Transpose(int mt[][10], int m, int n) {...}

It should be invoked by

Transpose(a, 4, 5);

Also, what is the 10 for? And, the statement

printf("ARRAY: %d", a[][5]);

is unlikely to work.

---

You should choose better names for your variables. Instead of m and n , use nRows and nColumns . Use row and column instead of i and j .

Answer 2

You can use the following code to do it.

#include<stdio.h>
// Print Matrix
void printArr(int *A, int row,int col)
{
    int i,j;
    for(i=0;i<row;i++)
    {
        printf("\n");
        for(j=0;j<col;j++)
            printf("%d\t",*(A+(col*i)+j));
    }
}

//Find the Transpose(TA) of Matrix(A) 
void Transpose(int *A,int *TA,int row,int col)
{
   int i,j;
   for(i=0;i<row;i++)
       for(j=0;j<col;j++)
       *(TA+(j*row)+i)=*(A+(col*i)+j);
}
// Start of Main
int main()
{
   int A[4][5]={{1,2,3,4,5},{6,7,8,9,10},{10,9,8,7,6},{5,4,3,2,1}};
   int *TA=malloc(sizeof(int)*4*5); // Allocate Memory for TA
   int i,j;
   printf("Matrix A:");
   printArr(A,4,5); //Print Array A
   Transpose(A,TA,4,5); //Call Transpose
   printf("\nTranspose Matrix A:"); 
   printArr(TA,5,4); // Print Array TA
   return 0;
}

Output:

Matrix A:
    1   2   3   4   5   
    6   7   8   9   10  
    10  9   8   7   6    
    5   4   3   2   1
Transpose Matrix A:
    1   6   10  5   
    2   7   9   4   
    3   8   8   3   
    4   9   7   2   
    5   10  6   1   

Answer 3

The C programming language does not remember the lengths of arrays like other programming languages do. That makes working with multidimensional arrays difficult.

To pass a multidimensional array as a parameter in C, you either have to know the dimensions of the array at compile time:

#define HEIGHT 10
#define WIDTH 13

void function_prototype(int M[HEIGHT][WIDTH]) {
  access M normally with M[y][x]
}

or you have to pass a single dimensional array and the lengths as parameters:

void function_prototype(int* M, int height, int width) {
  access M as M[y * width + x]
}

It's troublesome, but that's the price you pay for having extremely fast array access.