// For 0 <= r < numRows and 0 <= c < numCols, element (r,c) is 1 and
// all others are 0. If either of r or c is invalid, the zero matrix
// is created. This is a convenience for creating the standard
// Euclidean basis matrices; see also MakeUnit(int,int) and
// Unit(int,int).
public GMatrix(int numRows, int numCols, int r, int c)
{
this.numRows = numRows;
this.numCols = numCols;
this.elements = new GVector(numRows * numCols);
this.MakeUnit(r, c);
}
// Initialization to a diagonal matrix whose diagonal entries are the
// components of D, even when nonsquare.
public static void MakeDiagonal(GVector d, GMatrix m)
{
int numRows = m.NumRows;
int numCols = m.NumCols;
int numDiagonal = numRows <= numCols ? numRows : numCols;
m.MakeZero();
for (int i = 0; i < numDiagonal; ++i)
{
m[i, i] = d[i];
}
}
// U*V^T, U is N-by-1, V is M-by-1, result is N-by-M.
public static GMatrix OuterProduct(GVector u, GVector v)
{
GMatrix result = new GMatrix(u.Size, v.Size);
for (int r = 0; r < result.NumRows; ++r)
{
for (int c = 0; c < result.NumCols; ++c)
{
result[r, c] = u[r] * v[c];
}
}
return(result);
}
public GVector GetCol(int c)
{
if (0 <= c && c < this.numCols)
{
GVector vec = new GVector(this.numRows);
for (int r = 0; r < this.numRows; ++r)
{
vec[r] = this[r, c];
}
return(vec);
}
Debug.Assert(false, "Invalid index.");
return(new GVector(0));
}
public GVector GetRow(int r)
{
if (0 <= r && r < this.numRows)
{
GVector vec = new GVector(this.numCols);
for (int c = 0; c < this.numCols; ++c)
{
vec[c] = this[r, c];
}
return(vec);
}
Debug.Assert(false, "Invalid index.");
return(new GVector(0));
}
// D*M, D is square diagonal (stored as vector)
public static GMatrix MultiplyDM(GVector d, GMatrix m)
{
if (d.Size == m.NumRows)
{
GMatrix result = new GMatrix(m.NumRows, m.NumCols);
for (int r = 0; r < result.NumRows; ++r)
{
for (int c = 0; c < result.NumCols; ++c)
{
result[r, c] = d[r] * m[r, c];
}
}
return(result);
}
Debug.Assert(false, "Mismatched sizes.");
return(new GMatrix(0, 0));
}
public void SetCol(int c, GVector vec)
{
if (0 <= c && c < this.numCols)
{
if (vec.Size == this.NumRows)
{
for (int r = 0; r < this.numRows; ++r)
{
this[r, c] = vec[r];
}
return;
}
Debug.Assert(false, "Mismatched sizes.");
}
Debug.Assert(false, "Invalid index.");
}
// Member access by rows or by columns. The input vectors must have
// the correct number of elements for the matrix size.
public void SetRow(int r, GVector vec)
{
if (0 <= r && r < this.numRows)
{
if (vec.Size == this.NumCols)
{
for (int c = 0; c < this.numCols; ++c)
{
this[r, c] = vec[c];
}
return;
}
Debug.Assert(false, "Mismatched sizes.");
}
Debug.Assert(false, "Invalid index.");
}
// V^T*M
public static GVector operator *(GVector v, GMatrix m)
{
if (v.Size == m.NumRows)
{
GVector result = new GVector(m.NumCols);
for (int c = 0; c < m.NumCols; ++c)
{
result[c] = 0.0;
for (int r = 0; r < m.NumRows; ++r)
{
result[c] += v[r] * m[r, c];
}
}
return(result);
}
Debug.Assert(false, "Mismatched sizes.");
return(new GVector(0));
}
public GMatrix(int numRows, int numCols, double[] elements)
{
this.numRows = numRows;
this.numCols = numCols;
this.elements = new GVector(elements);
}
//// The table is length zero and mNumRows and mNumCols are set to zero.
//public GMatrix()
//{
//}
// The table is length numRows*numCols and the elements are
// initialized to zero.
public GMatrix(int numRows, int numCols)
{
this.numRows = numRows;
this.numCols = numCols;
this.elements = new GVector(numRows * numCols);
}
