7.8.4.13. statsmodels.tsa.arima_process.lpol2index¶

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

remove zeros from lagpolynomial, squeezed representation with index

Parameters:	ar : array_like coefficients of lag polynomial
Returns:	coeffs : array non-zero coefficients of lag polynomial index : array index (lags) of lagpolynomial with non-zero elements