# EntropyTruncation

class EntropyTruncation(*, rounding_threshold=0.5)

Configuration for entropy-based truncation. The entropy truncation method first calculates the entropy $$E$$ of the singular values; it then calculates the value $$2^E$$ and rounds the value to an integer $$n_{\mathrm{sv}}$$, determined by the rounding threshold you choose; it finally uses $$n_{\mathrm{sv}}$$ as the truncation value.

Variables

rounding_threshold (float, optional) – The rounding threshold, between 0 and 1 (inclusive). When rounding the value $$2^E$$, the floor of $$2^E$$ plus the rounding threshold is taken. Therefore a small value leads to rounding down, while a large value leads to rounding up. Defaults to 0.5.