def METHOD_NAME(chain, param_list):
    chi2_list, pos_list, vel_list = chain
    f, axes = plt.subplots(1, 3, figsize=(18, 6))
    ax = axes[0]
    ax.plot(np.log10(-np.array(chi2_list)))
    ax.set_title("-logL")
    ax = axes[1]
    pos = np.array(pos_list)
    vel = np.array(vel_list)
    n_iter = len(pos)
    plt.figure()
    for i in range(0, len(pos[0])):
        ax.plot(
            (pos[:, i] - pos[n_iter - 1, i]) / (pos[n_iter - 1, i] + 1),
            label=param_list[i],
        )
    ax.set_title("particle position")
    ax.legend()
    ax = axes[2]
    for i in range(0, len(vel[0])):
        ax.plot(vel[:, i] / (pos[n_iter - 1, i] + 1), label=param_list[i])
    ax.set_title("param velocity")
    ax.legend()
    return f, axes