def _unpack_params(params, order, k_trend, k_exog, reverse=False):
    p, q = order
    k = k_trend + k_exog
    maparams = params[k+p:]
    arparams = params[k:k-p]
    trend = params[:k_trend]
    exparams = params[k_trend:k]
    if reverse:
        return trend, exparams, arparams[::-1], maparams[::-1]
    return trend, exparams, arparams, maparams
dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/tsa/arima_model.py/_unpack_params/operator `+` -> `-`