B ¤ŠãZã@sdZddd„ZdS)zDCollection of alternative implementations for time series analysis TcCsbddlm}t |¡}|r&|| ¡}| ||ddd…¡t|ƒdt|ƒd…|jddS)a`autocovariance function with call to fftconvolve, biased Parameters ---------- x : array_like timeseries, signal demean : boolean If true, then demean time series Returns ------- acovf : array autocovariance for data, same length as x might work for nd in parallel with time along axis 0 é)ÚsignalNéÿÿÿÿéé )ZscipyrZnpZasarrayZmeanZ fftconvolveÚlenÚshape)ÚxZdemeanr©r ú>lib/python3.7/site-packages/statsmodels/sandbox/archive/tsa.pyÚ acovf_ffts    r N)T)Ú__doc__r r r r r Ús