// Produces a random K81 transition matrix with diagonal entries >= 0.7.
void K81_random_edge(TMatrix &tm) {
double a,b,c,d;
double dmin = 0.7;
do {
a = uniform_real(dmin, 1);
b = uniform_real(0, 1-dmin);
c = uniform_real(0, 1-dmin);
d = 1 - a - b - c;
} while (d < 0);
K81_matrix(a,b,c,d,tm);
}
//This method executes the policy
pair<vector<float>,float> CDACN::policy(const Window &window)
{
if(uniform_real(engine)<exploration_rate_ or not window.full())
return explore();
else
return exploit(window);
}
// Random K81 transition matrix for a given branch length
void K81_random_edge_length(double len, TMatrix &tm) {
double a,b,c,d;
double K, x1, x2, x3, s, m, M, p, q;
K = exp(-4*len);
// s is the only real root of x(x+1)^2 - 4K = 0
s = - 2./3. + 1./3.*pow(1. + 54.*K + 6.*sqrt(3.*K + 81.*K*K), 1./3.)
+ 1./3.*pow(1. + 54.*K - 6.*sqrt(3.*K + 81.*K*K), 1./3.);
if (s > 1 || s < 0) {
std::cout << "Error: Something strange happened at K81_random_edge_length. Bad s.";
std::cout << std::endl;
}
x1 = uniform_real(s, 1);
p = sqrt((x1*(x1-1)*(x1-1)+4*K)/x1);
q = sqrt((x1*(x1+1)*(x1+1)-4*K)/x1);
m = 0.5*(x1 + std::max<double>(1-q, p-1));
M = 0.5*(1 + std::min<double>(p-x1, q+x1));
if (m > M || m < 0) {
std::cout << "Error: Something strange happened at K81_random_edge_length: bad bounds m and M.";
std::cout << std::endl;
}
x2 = uniform_real(m, M);
double gamma;
gamma = uniform_real(0,1);
if (gamma > 0.5) x1 = -x1;
gamma = uniform_real(0,1);
if (gamma > 0.5) x2 = -x2;
x3 = K/(x1*x2);
b = 0.25*(1 - x1 - x2 + x3);
c = 0.25*(1 - x1 + x2 - x3);
d = 0.25*(1 + x1 - x2 - x3);
a = 1 - b - c - d;
K81_matrix(a,b,c,d,tm);
}
fcppt::random::distribution::parameters::uniform_real<
FloatType
>
fcppt::random::distribution::parameters::uniform_real<
FloatType
>::convert_to(
distribution const &_dist
)
{
return
uniform_real(
min(
fcppt::random::distribution::decorated_value(
_dist.a()
)
),
sup(
fcppt::random::distribution::decorated_value(
_dist.b()
)
)
);
}
