butools.ph.CheckPHRepresentation¶

butools.ph.CheckPHRepresentation()¶

Matlab:	r = CheckPHRepresentation(alpha, A, prec)
Mathematica:	r = CheckPHRepresentation[alpha, A, prec]
Python/Numpy:	r = CheckPHRepresentation(alpha, A, prec)

Checks if the given vector and matrix define a valid phase- type representation.

Parameters:	alpha : matrix, shape (1,M) Initial vector of the phase-type distribution to check A : matrix, shape (M,M) Transient generator of the phase-type distribution to check prec : double, optional Numerical precision. The default value is 1e-14.
Returns:	r : bool True, if vector alpha is a probability vector and matrix A is a transient generator, and they have the same size.

Examples

For Matlab:

>>> a = [0.2];
>>> A = [-1, 1; 1, -2];
>>> flag = CheckPHRepresentation(a, A);
CheckPHRepresentation:the vector and the matrix have different sizes!
>>> disp(flag);
     0
>>> a = [0.2,0.7];
>>> A = [-1, 1; 1, -2];
>>> flag = CheckPHRepresentation(a, A);
>>> disp(flag);
     1

For Mathematica:

>>> a = {0.2};
>>> A = {{-1, 1},{1, -2}};
>>> flag = CheckPHRepresentation[a, A];
"CheckPHRepresentation: the vector and the matrix have different sizes!"
>>> Print[flag];
False
>>> a = {0.2,0.7};
>>> A = {{-1, 1},{1, -2}};
>>> flag = CheckPHRepresentation[a, A];
>>> Print[flag];
True

For Python/Numpy:

>>> a = ml.matrix([[0.2]])
>>> A = ml.matrix([[-1, 1],[1, -2]])
>>> flag = CheckPHRepresentation(a, A)
CheckPHRepresentation: The vector and the matrix have different sizes!
>>> print(flag)
False
>>> a = ml.matrix([[0.2,0.7]])
>>> A = ml.matrix([[-1, 1],[1, -2]])
>>> flag = CheckPHRepresentation(a, A)
>>> print(flag)
True