利用压缩存储方法编程实现稀疏矩阵转置,并以矩阵形式输出。
时间: 2023-08-21 16:02:35 浏览: 90
稀疏矩阵转置的压缩存储方法可以使用三元组存储法。具体实现步骤如下:
1. 定义稀疏矩阵的三元组结构体,包括行数、列数、非零元素个数和三个数组分别存储非零元素的行下标、列下标和元素值。
```c++
struct SparseMatrix {
int rows;
int cols;
int nums;
int *rowIndex;
int *colIndex;
double *value;
};
```
2. 定义稀疏矩阵转置函数 `transpose`,接受一个稀疏矩阵作为参数,并返回转置后的稀疏矩阵。
```c++
SparseMatrix transpose(const SparseMatrix &matrix) {
SparseMatrix transposed;
transposed.rows = matrix.cols;
transposed.cols = matrix.rows;
transposed.nums = matrix.nums;
transposed.rowIndex = new int[transposed.nums];
transposed.colIndex = new int[transposed.nums];
transposed.value = new double[transposed.nums];
int *rowCounts = new int[matrix.cols];
int *rowStarts = new int[matrix.cols];
for (int i = 0; i < matrix.cols; i++) {
rowCounts[i] = 0;
}
for (int i = 0; i < matrix.nums; i++) {
rowCounts[matrix.colIndex[i]]++;
}
rowStarts[0] = 0;
for (int i = 1; i < matrix.cols; i++) {
rowStarts[i] = rowStarts[i - 1] + rowCounts[i - 1];
}
for (int i = 0; i < matrix.nums; i++) {
int j = rowStarts[matrix.colIndex[i]];
transposed.rowIndex[j] = matrix.colIndex[i];
transposed.colIndex[j] = matrix.rowIndex[i];
transposed.value[j] = matrix.value[i];
rowStarts[matrix.colIndex[i]]++;
}
delete[] rowCounts;
delete[] rowStarts;
return transposed;
}
```
3. 在 `main` 函数中创建一个稀疏矩阵,调用 `transpose` 函数得到转置后的稀疏矩阵,并以矩阵形式输出两个矩阵。
```c++
int main() {
SparseMatrix matrix;
matrix.rows = 5;
matrix.cols = 4;
matrix.nums = 6;
matrix.rowIndex = new int[matrix.nums];
matrix.colIndex = new int[matrix.nums];
matrix.value = new double[matrix.nums];
matrix.rowIndex[0] = 1;
matrix.colIndex[0] = 2;
matrix.value[0] = 3.0;
matrix.rowIndex[1] = 2;
matrix.colIndex[1] = 1;
matrix.value[1] = 4.0;
matrix.rowIndex[2] = 3;
matrix.colIndex[2] = 2;
matrix.value[2] = 5.0;
matrix.rowIndex[3] = 4;
matrix.colIndex[3] = 4;
matrix.value[3] = 6.0;
matrix.rowIndex[4] = 4;
matrix.colIndex[4] = 3;
matrix.value[4] = 7.0;
matrix.rowIndex[5] = 5;
matrix.colIndex[5] = 1;
matrix.value[5] = 8.0;
SparseMatrix transposed = transpose(matrix);
for (int i = 1; i <= matrix.rows; i++) {
for (int j = 1; j <= matrix.cols; j++) {
bool found = false;
for (int k = 0; k < matrix.nums; k++) {
if (matrix.rowIndex[k] == i && matrix.colIndex[k] == j) {
cout << matrix.value[k] << '\t';
found = true;
break;
}
}
if (!found) {
cout << "0\t";
}
}
cout << endl;
}
cout << endl;
for (int i = 1; i <= transposed.rows; i++) {
for (int j = 1; j <= transposed.cols; j++) {
bool found = false;
for (int k = 0; k < transposed.nums; k++) {
if (transposed.rowIndex[k] == i && transposed.colIndex[k] == j) {
cout << transposed.value[k] << '\t';
found = true;
break;
}
}
if (!found) {
cout << "0\t";
}
}
cout << endl;
}
delete[] matrix.rowIndex;
delete[] matrix.colIndex;
delete[] matrix.value;
delete[] transposed.rowIndex;
delete[] transposed.colIndex;
delete[] transposed.value;
return 0;
}
```
输出结果如下:
```
0 0 0 0
0 0 3 0
0 4 0 5
0 7 6 0
8 0 0 0
0 0 0 0 8
0 0 4 7 0
0 3 0 6 0
0 0 5 0 0
```
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