statsmodels.tsa.arima_process.lpol2index¶

statsmodels.tsa.arima_process.lpol2index(ar)[source]¶

Remove zeros from lag polynomial

Parameters:¶

ararray_like

coefficients of lag polynomial

Returns:¶

coeffsndarray

non-zero coefficients of lag polynomial

indexndarray

index (lags) of lag polynomial with non-zero elements