+++ /dev/null
-EMGLLF_R = function(phiInit,rhoInit,piInit,gamInit,mini,maxi,gamma,lambda,X,Y,tau)
-{
- # Matrix dimensions
- n = dim(X)[1]
- p = dim(phiInit)[1]
- m = dim(phiInit)[2]
- k = dim(phiInit)[3]
-
- # Outputs
- phi = phiInit
- rho = rhoInit
- pi = piInit
- llh = -Inf
- S = array(0, dim=c(p,m,k))
-
- # Algorithm variables
- gam = gamInit
- Gram2 = array(0, dim=c(p,p,k))
- ps2 = array(0, dim=c(p,m,k))
- X2 = array(0, dim=c(n,p,k))
- Y2 = array(0, dim=c(n,m,k))
- EPS = 1e-15
-
- for (ite in 1:maxi)
- {
- # Remember last pi,rho,phi values for exit condition in the end of loop
- Phi = phi
- Rho = rho
- Pi = pi
-
- # Calcul associé à Y et X
- for (r in 1:k)
- {
- for (mm in 1:m)
- Y2[,mm,r] = sqrt(gam[,r]) * Y[,mm]
- for (i in 1:n)
- X2[i,,r] = sqrt(gam[i,r]) * X[i,]
- for (mm in 1:m)
- ps2[,mm,r] = crossprod(X2[,,r],Y2[,mm,r])
- for (j in 1:p)
- {
- for (s in 1:p)
- Gram2[j,s,r] = crossprod(X2[,j,r], X2[,s,r])
- }
- }
-
- ##########
- #Etape M #
- ##########
-
- # Pour pi
- b = sapply( 1:k, function(r) sum(abs(phi[,,r])) )
- gam2 = colSums(gam)
- a = sum(gam %*% log(pi))
-
- # Tant que les props sont negatives
- kk = 0
- pi2AllPositive = FALSE
- while (!pi2AllPositive)
- {
- pi2 = pi + 0.1^kk * ((1/n)*gam2 - pi)
- pi2AllPositive = all(pi2 >= 0)
- kk = kk+1
- }
-
- # t(m) la plus grande valeur dans la grille O.1^k tel que ce soit décroissante ou constante
- while( kk < 1000 && -a/n + lambda * sum(pi^gamma * b) <
- -sum(gam2 * log(pi2))/n + lambda * sum(pi2^gamma * b) )
- {
- pi2 = pi + 0.1^kk * (1/n*gam2 - pi)
- kk = kk + 1
- }
- t = 0.1^kk
- pi = (pi + t*(pi2-pi)) / sum(pi + t*(pi2-pi))
-
- #Pour phi et rho
- for (r in 1:k)
- {
- for (mm in 1:m)
- {
- ps = 0
- for (i in 1:n)
- ps = ps + Y2[i,mm,r] * sum(X2[i,,r] * phi[,mm,r])
- nY2 = sum(Y2[,mm,r]^2)
- rho[mm,mm,r] = (ps+sqrt(ps^2+4*nY2*gam2[r])) / (2*nY2)
- }
- }
-
- for (r in 1:k)
- {
- for (j in 1:p)
- {
- for (mm in 1:m)
- {
- S[j,mm,r] = -rho[mm,mm,r]*ps2[j,mm,r] + sum(phi[-j,mm,r] * Gram2[j,-j,r])
- if (abs(S[j,mm,r]) <= n*lambda*(pi[r]^gamma))
- phi[j,mm,r]=0
- else if(S[j,mm,r] > n*lambda*(pi[r]^gamma))
- phi[j,mm,r] = (n*lambda*(pi[r]^gamma)-S[j,mm,r]) / Gram2[j,j,r]
- else
- phi[j,mm,r] = -(n*lambda*(pi[r]^gamma)+S[j,mm,r]) / Gram2[j,j,r]
- }
- }
- }
-
- ##########
- #Etape E #
- ##########
-
- # Precompute det(rho[,,r]) for r in 1...k
- detRho = sapply(1:k, function(r) det(rho[,,r]))
-
- sumLogLLH = 0
- for (i in 1:n)
- {
- # Update gam[,]
- sumGamI = 0
- for (r in 1:k)
- {
- gam[i,r] = pi[r]*exp(-0.5*sum((Y[i,]%*%rho[,,r]-X[i,]%*%phi[,,r])^2))*detRho[r]
- sumGamI = sumGamI + gam[i,r]
- }
- sumLogLLH = sumLogLLH + log(sumGamI) - log((2*base::pi)^(m/2))
- if (sumGamI > EPS) #else: gam[i,] is already ~=0
- gam[i,] = gam[i,] / sumGamI
- }
-
- sumPen = sum(pi^gamma * b)
- last_llh = llh
- llh = -sumLogLLH/n + lambda*sumPen
- dist = ifelse( ite == 1, llh, (llh-last_llh) / (1+abs(llh)) )
- Dist1 = max( (abs(phi-Phi)) / (1+abs(phi)) )
- Dist2 = max( (abs(rho-Rho)) / (1+abs(rho)) )
- Dist3 = max( (abs(pi-Pi)) / (1+abs(Pi)) )
- dist2 = max(Dist1,Dist2,Dist3)
-
- if (ite >= mini && (dist >= tau || dist2 >= sqrt(tau)))
- break
- }
-
- affec = apply(gam, 1, which.max)
- list( "phi"=phi, "rho"=rho, "pi"=pi, "llh"=llh, "S"=S, "affec"=affec )
-}