在C中将数据从一个矩阵复制到另一个矩阵

I have two matrix dynamically allocated.I want to copy all the data from the first matrix and center it by a border to the second one.Here is my code which apparently does not work properly so I would be grateful for some help:

我有两个动态分配的矩阵。我想把所有的数据从第一个矩阵拷贝到第二个矩阵中间。这是我的代码，显然不能正常工作，因此我将感谢一些帮助:

The first matrix:

第一个矩阵:

    unsigned char ** sudo=(unsigned char **) malloc (width*sizeof (unsigned char*));

if ( sudo != NULL){
    for (k=0; k<width ;k++){
        sudo[k] =(unsigned char*) calloc (height,sizeof (unsigned char));
    }
}

The second one:

第二个:

unsigned char ** fmatr=(unsigned char **) malloc ((width+border)*sizeof (unsigned char*));

if ( fmatr != NULL){
    for (k=0; k<(width+border) ;k++){
        fmatr[k] =(unsigned char*) calloc ((height+border),sizeof (unsigned char));
    }
}

How I center first matrix in the middle of the second one:

我如何把第一矩阵放在第二点的中间

    for(i=0,k=0;i<(width+border);i++,k++){
      for(j=0,l=0;j<(height+border);j++,l++){
        if((i>(2*border)) && (j>(2*border))){
            fmatr[i][j]=sudo[k][l];
        }
    }
}

Any ideas?

什么好主意吗?

1 个解决方案

#1

Since the first matrix has width x height entries, you want to loop from 0 to width-1 (not width-1+border) and from 0 to height-1 (not height-1+border). Similarly, you want to add border/2 to the index of the second array when assigning.

由于第一个矩阵有宽度x高度条目，所以您希望从0到宽度-1(不是宽度-1+边框)以及从0到高度-1(不是高度-1+边框)进行循环。类似地，您希望在赋值时向第二个数组的索引添加border/2。

for(i=0;i<width;i++){
  for(j=0;j<height;j++){
    fmatr[i+(border/2)][j+(border/2)]=sudo[i][j];
  }
}