public void Demo2()
{
foreach (var f in new[] { DoubleFactory2D.Dense, DoubleFactory2D.Sparse })
{
const DoubleMatrix2D N = null;
DoubleMatrix2D a = f.Make(2, 2, 1);
DoubleMatrix2D b = f.Make(4, 4, 2);
DoubleMatrix2D c = f.Make(4, 3, 3);
DoubleMatrix2D d = f.Make(2, 2, 4);
var parts1 = new[] { new[] { N, a, N }, new[] { b, N, c }, new[] { N, d, N } };
DoubleMatrix2D matrix = f.Compose(parts1);
var sm = matrix.ToString();
a.Assign(9);
b.Assign(9);
c.Assign(9);
d.Assign(9);
f.Decompose(parts1, matrix);
var sa = a.ToString();
var sb = b.ToString();
var sc = c.ToString();
var sd = d.ToString();
}
}
/// <summary>
/// A = A * s <=> A[row,col] = A[row,col] * s
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Mult(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Mult(s));
}
/// <summary>
/// A = A - s <=> A[row,col] = A[row,col] - s
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Minus(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Minus(s));
}
/// <summary>
/// A[row,col] = A[row,col] < B[row,col] ? 1 : 0
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Less(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Less);
}
public void Dscal(double alpha, DoubleMatrix2D A)
{
A.Assign(F1.Mult(alpha));
}
/// <summary>
/// A[row,col] = System.Math.Abs(A[row,col])
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Abs(DoubleMatrix2D A)
{
return A.Assign(F1.Abs);
}
/// <summary>
/// A = A<sup>s</sup> <=> A[row,col] = System.Math.Pow(A[row,col], s)
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Pow(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Pow(s));
}
/// <summary>
/// A = A + B <=> A[row,col] = A[row,col] + B[row,col]
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Plus(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Plus);
}
/// <summary>
/// A[row,col] = A[row,col] == s ? 1 : 0; ignores tolerance.
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Equals(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Equals(s));
}
/// <summary>
/// A = A / B <=> A[row,col] = A[row,col] / B[row,col]
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Div(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Div);
}
/// <summary>
/// A = A / s <=> A[row,col] = A[row,col] / s
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Div(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Div(s));
}
public void Dcopy(DoubleMatrix2D A, DoubleMatrix2D B)
{
B.Assign(A);
}
public void Daxpy(double alpha, DoubleMatrix2D A, DoubleMatrix2D B)
{
B.Assign(A, F2.PlusMult(alpha));
}
public void Assign(DoubleMatrix2D A, DoubleMatrix2D B, Cern.Colt.Function.DoubleDoubleFunction function)
{
A.Assign(B, function);
}
/// <summary>
/// A = A * B <=> A[row,col] = A[row,col] * B[row,col]
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Mult(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Mult);
}
/// <summary>
/// A = -A <=> A[row,col] = -A[row,col]
/// </summary>
/// <param name="A"></param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Negate(DoubleMatrix2D A)
{
return A.Assign(F1.Mult(-1));
}
/// <summary>
/// A[row,col] = A[row,col] == B[row,col] ? 1 : 0; ignores tolerance.
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Equals(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Equals);
}
/// <summary>
/// A = A + B*s <=> A[row,col] = A[row,col] + B[row,col]*s
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D PlusMult(DoubleMatrix2D A, DoubleMatrix2D B, double s)
{
return A.Assign(B, F2.PlusMult(s));
}
/// <summary>
/// A[row,col] = A[row,col] > s ? 1 : 0
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Greater(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Greater(s));
}
/// <summary>
/// A = A<sup>B</sup> <=> A[row,col] = System.Math.Pow(A[row,col], B[row,col])
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Pow(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Pow);
}
/// <summary>
/// A[row,col] = A[row,col] > B[row,col] ? 1 : 0
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="B">the matrix to stay unaffected.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Greater(DoubleMatrix2D A, DoubleMatrix2D B)
{
return A.Assign(B, F2.Greater);
}
/// <summary>
/// A[row,col] = A[row,col] < s ? 1 : 0
/// </summary>
/// <param name="A">the matrix to modify.</param>
/// <param name="s">the scalar; can have any value.</param>
/// <returns><i>A</i> (for convenience only).</returns>
public static DoubleMatrix2D Less(DoubleMatrix2D A, double s)
{
return A.Assign(F1.Less(s));
}
/// <summary>
/// Linear algebraic matrix power; <i>B = A<sup>k</sup> <==> B = A*A*...*A</i>.
/// <ul>
/// <li><i>p >= 1: B = A*A*...*A</i>.</li>
/// <li><i>p == 0: B = identity matrix</i>.</li>
/// <li><i>p < 0: B = pow(inverse(A),-p)</i>.</li>
/// </ul>
/// Implementation: Based on logarithms of 2, memory usage minimized.
/// </summary>
/// <param name="A">the source matrix; must be square; stays unaffected by this operation.</param>
/// <param name="p">the exponent, can be any number.</param>
/// <returns><i>B</i>, a newly constructed result matrix; storage-independent of <i>A</i>.</returns>
///<exception cref="ArgumentException">if <i>!property().isSquare(A)</i>.</exception>
public static DoubleMatrix2D Pow(DoubleMatrix2D A, int p)
{
// matrix multiplication based on log2 method: A*A*....*A is slow, ((A * A)^2)^2 * ..D is faster
// allocates two auxiliary matrices as work space
IBlas blas = SmpBlas.smpBlas; // for parallel matrix mult; if not initialized defaults to sequential blas
Property.DEFAULT.CheckSquare(A);
if (p < 0)
{
A = Inverse(A);
p = -p;
}
if (p == 0)
{
return(DoubleFactory2D.Dense.Identity(A.Rows));
}
DoubleMatrix2D T = A.Like(); // temporary
if (p == 1)
{
return(T.Assign(A)); // safes one auxiliary matrix allocation
}
if (p == 2)
{
blas.Dgemm(false, false, 1, A, A, 0, T); // mult(A,A); // safes one auxiliary matrix allocation
return(T);
}
int k = Cern.Colt.Bitvector.QuickBitVector.MostSignificantBit(p); // index of highest bit in state "true"
/*
* this is the naive version:
* DoubleMatrix2D B = A.Copy();
* for (int i=0; i<p-1; i++) {
* B = mult(B,A);
* }
* return B;
*/
// here comes the optimized version:
//cern.colt.Timer timer = new cern.colt.Timer().start();
int i = 0;
while (i <= k && (p & (1 << i)) == 0)
{ // while (bit i of p == false)
// A = mult(A,A); would allocate a lot of temporary memory
blas.Dgemm(false, false, 1, A, A, 0, T); // A.zMult(A,T);
DoubleMatrix2D swap = A; A = T; T = swap; // swap A with T
i++;
}
DoubleMatrix2D B = A.Copy();
i++;
for (; i <= k; i++)
{
// A = mult(A,A); would allocate a lot of temporary memory
blas.Dgemm(false, false, 1, A, A, 0, T); // A.zMult(A,T);
DoubleMatrix2D swap = A; A = T; T = swap; // swap A with T
if ((p & (1 << i)) != 0)
{ // if (bit i of p == true)
// B = mult(B,A); would allocate a lot of temporary memory
blas.Dgemm(false, false, 1, B, A, 0, T); // B.zMult(A,T);
swap = B; B = T; T = swap; // swap B with T
}
}
//timer.stop().Display();
return(B);
}
