Source code for qurry.process.hadamard_test.entangled_entropy

"""Post Processing - Hadamard Test - Entangled Entropy
(:mod:`qurry.process.hadamard_test.entangled_entropy`)

"""

from typing import Optional
import numpy as np
import tqdm


from ..availability import PostProcessingBackendLabel
from .purity_echo_core import purity_echo_core, DEFAULT_PROCESS_BACKEND



[docs]
def hadamard_entangled_entropy(
    shots: int,
    counts: list[dict[str, int]],
    backend: PostProcessingBackendLabel = DEFAULT_PROCESS_BACKEND,
    pbar: Optional[tqdm.tqdm] = None,
) -> dict[str, float]:
    """Calculate entangled entropy with more information combined.
    The entropy we compute is the Second Order Rényi Entropy.

    Args:
        shots (int):
            Shots of the experiment on quantum machine.
        counts (list[dict[str, int]]):
            Counts of the experiment on quantum machine.
        backend (PostProcessingBackendLabel, optional):
            Backend of the postprocessing. Defaults to DEFAULT_PROCESS_BACKEND.
        pbar (Optional[tqdm.tqdm], optional):
            Progress bar. Defaults to None.

    Raises:
        ValueError: Get degree neither 'int' nor 'tuple[int, int]'.
        ValueError: Measure range does not contain subsystem.

    Returns:
        dict[str, float]: Quantity of the experiment.
    """

    if isinstance(pbar, tqdm.tqdm):
        pbar.set_description_str("Calculate entropy by Hadamard Test.")
    purity = purity_echo_core(shots, counts, backend)

    quantity = {
        "purity": purity,
        "entropy": -np.log2(purity),
    }
    return quantity