src/main/python/systemds/scuro/representations/hadamard.py

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from typing import List

import numpy as np

from systemds.scuro.modality.modality import Modality

from systemds.scuro.representations.fusion import Fusion

from systemds.scuro.drsearch.operator_registry import register_fusion_operator


@register_fusion_operator()
class Hadamard(Fusion):
    def __init__(self):
        """
        Combines modalities using elementwise multiply (Hadamard product)
        """
        super().__init__("Hadamard")
        self.needs_alignment = True  # zero padding falsifies the result
        self.commutative = True
        self.associative = True

    def transform(self, modalities: List[Modality], train_indices=None):
        # TODO: check for alignment in the metadata
        fused_data = np.prod([m.data for m in modalities], axis=0)

        return fused_data