public JZ Multiply(JZ other) //矩阵乘法
{ // 检查行列数是否符合要求
if (numColumns != other.GetNumRows())
{
throw new Exception("矩阵的行/列数不匹配。");
}
JZ result = new JZ(numRows, other.GetNumColumns());
double value;
for (int i = 0; i < result.GetNumRows(); ++i)
{
for (int j = 0; j < other.GetNumColumns(); ++j)
{
value = 0.0;
for (int k = 0; k < numColumns; ++k)
{
value += GetElement(i, k) * other.GetElement(k, j);
}
result.SetElement(i, j, value);
}
}
return(result);
}
public JZ Multiply(double val) //数乘矩阵
{ // 构造目标矩阵
JZ result = new JZ(this); // copy ourselves
// 进行数乘
for (int i = 0; i < numRows; ++i)
{
for (int j = 0; j < numColumns; ++j)
{
result.SetElement(i, j, GetElement(i, j) * val);
}
}
return(result);
}
public JZ Transpose() //转制
{ // 构造目标矩阵
JZ Trans = new JZ(numColumns, numRows);
// 转置各元素
for (int i = 0; i < numRows; ++i)
{
for (int j = 0; j < numColumns; ++j)
{
Trans.SetElement(j, i, GetElement(i, j));
}
}
return(Trans);
}
public JZ Subtract(JZ other)//矩阵减法
{
if (numColumns != other.GetNumColumns() || numRows != other.GetNumRows())
{
throw new Exception("矩阵的行/列数不匹配。");
}
// 构造结果矩阵
JZ result = new JZ(this);
// 进行减法
for (int i = 0; i < numRows; ++i)
{
for (int j = 0; j < numColumns; ++j)
{
result.SetElement(i, j, GetElement(i, j) - other.GetElement(i, j));
}
}
return(result);
}
public JZ Add(JZ other) //矩阵加法
{ // 检查行列数是否相等
if (numColumns != other.GetNumColumns() || numRows != other.GetNumRows())
{
throw new Exception("矩阵的行/列数不匹配。");
}
// 构造结果矩阵
JZ result = new JZ(this);
// 进行加法
for (int i = 0; i < numRows; ++i)
{
for (int j = 0; j < numColumns; ++j)
{
result.SetElement(i, j, GetElement(i, j) + other.GetElement(i, j));
}
}
return(result);
}
public JZ InvertGaussJordan() //矩阵的求逆
{
int i, j, k, l, u, v;
double d = 0.0, p = 0.0;
int[] pnRow = new int[numColumns];
int[] pnCol = new int[numColumns];
{
for (k = 0; k <= numColumns - 1; k++)
{
d = 0.0;
for (i = k; i <= numColumns - 1; i++)
{
for (j = k; j <= numColumns - 1; j++)
{
l = i * numColumns + j; p = Math.Abs(elements[l]);
if (p > d)
{
d = p;
pnRow[k] = i;
pnCol[k] = j;
}
}
}
if (d == 0.0)
{
throw new Exception("矩阵不可逆。");
}
if (pnRow[k] != k)
{
for (j = 0; j <= numColumns - 1; j++)
{
u = k * numColumns + j;
v = pnRow[k] * numColumns + j;
p = elements[u];
elements[u] = elements[v];
elements[v] = p;
}
}
if (pnCol[k] != k)
{
for (i = 0; i <= numColumns - 1; i++)
{
u = i * numColumns + k;
v = i * numColumns + pnCol[k];
p = elements[u];
elements[u] = elements[v];
elements[v] = p;
}
}
l = k * numColumns + k;
elements[l] = 1.0 / elements[l];
for (j = 0; j <= numColumns - 1; j++)
{
if (j != k)
{
u = k * numColumns + j;
elements[u] = elements[u] * elements[l];
}
}
for (i = 0; i <= numColumns - 1; i++)
{
if (i != k)
{
for (j = 0; j <= numColumns - 1; j++)
{
if (j != k)
{
u = i * numColumns + j;
elements[u] = elements[u] - elements[i * numColumns + k] * elements[k * numColumns + j];
}
}
}
}
for (i = 0; i <= numColumns - 1; i++)
{
if (i != k)
{
u = i * numColumns + k;
elements[u] = -elements[u] * elements[l];
}
}
}
for (k = numColumns - 1; k >= 0; k--)
{
if (pnCol[k] != k)
{
for (j = 0; j <= numColumns - 1; j++)
{
u = k * numColumns + j;
v = pnCol[k] * numColumns + j;
p = elements[u];
elements[u] = elements[v];
elements[v] = p;
}
}
if (pnRow[k] != k)
{
for (i = 0; i <= numColumns - 1; i++)
{
u = i * numColumns + k;
v = i * numColumns + pnRow[k];
p = elements[u];
elements[u] = elements[v];
elements[v] = p;
}
}
}
}
JZ result = new JZ(numRows, numColumns);
for (int a = 0; a < numRows; ++a)
{
for (int b = 0; b < numColumns; ++b)
{
result.SetElement(a, b, GetElement(a, b));
}
}
return(result);
}