{'fraction_non_alphanumeric': 0.017432646592709985, 'fraction_numerical': 0.0, 'mean_word_length': 5.795698924731183, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Stable factorization of Hankel and Hankel-like matrices

This paper gives displacement structure algorithms for the factorization positive definite and indefinite Hankel and Hankel- like matrices. The positive definite algorithm uses orthogonal symplectic transformations in place of the (Sigma) -orthogonal transformations used in Toeplitz algorithms. The indefinite algorithm uses a look-ahead step and is based on the observation that displacement structure algorithms for Hankel factorization have a natural and simple block generalization. Both algorithms can be applied to Hankel-like matrices of arbitrary displacement rank.