Converts a single time series into a bag of words.
series_to_wordbag(ts, w_size, paa_size, a_size, nr_strategy, n_threshold)
the timeseries.
the sliding window size.
the PAA size.
the alphabet size.
the NR strategy.
the normalization threshold.
Senin Pavel and Malinchik Sergey, SAX-VSM: Interpretable Time Series Classification Using SAX and Vector Space Model. Data Mining (ICDM), 2013 IEEE 13th International Conference on, pp.1175,1180, 7-10 Dec. 2013.
Salton, G., Wong, A., Yang., C., A vector space model for automatic indexing. Commun. ACM 18, 11, 613-620, 1975.