def _mmlhs(x_start, population, generations):
    x_best = x_start
    phi_best = x_start.mmphi()
    n = x_start.shape[1]

    level_off = floor(0.85*generations)
    for it in range(generations):

        if it < level_off and level_off > 1.:
            mutations = int(round(1+(0.5*n-1)*(level_off-it)/(level_off-1)))
        else:
            mutations = 1

        x_improved = x_best
        phi_improved = phi_best

        for offspring in range(population):
            x_try = x_best.perturb(mutations)
            phi_try = x_try.mmphi()

            if phi_try < phi_improved:
                x_improved = x_try
                phi_improved = phi_try

        if phi_improved < phi_best:
            phi_best = phi_improved
            x_best = x_improved

    return x_best
Return the key strings
dataset/ETHPy150Open OpenMDAO/OpenMDAO-Framework/openmdao.lib/src/openmdao/lib/doegenerators/optlh.py/_mmlhs--crossover with--dataset/ETHPy150Open saltstack/salt/salt/wheel/key.py/key_str