Return matrix G(i,j), the mixture density for segment between points (i+1) to j : $$G(i,j) = \sum_{p=1}^P \log (\pi_p f(y^{ij};\theta_p))$$ Rq: this density if factorized in order to avoid numerical zeros in the log
Gmixt_simultanee(Don, lmin, phi)
a matrix
the bivariate signal
the minimum size for a segment
the parameters of the mixture