GAMMA(indbeta,:) = GAMMA(indbeta,:)/GAMMA(indbeta,alpha);
    GAMMAMOINS = [GAMMA(1:indbeta-1,:);GAMMA(indbeta+1:m,:)];
    GAMMAMOINS = GAMMAMOINS - GAMMAMOINS(:,alpha) * GAMMA(indbeta,:);
    GAMMA = [GAMMAMOINS(1:indbeta-1,:); GAMMA(indbeta,:); GAMMAMOINS(indbeta:m-1,:)];
    %
    z = c(JB)'*GAMMA(:,JN);
    pentes = c(JN)' -z;