def fit(self, X, truth, reference):
        H_s, _ = np.histogramdd(X[truth == 1], bins=self.bins, normed=False)
        H_b, _ = np.histogramdd(X[truth == 0], bins=self.bins, normed=False)
        H_ref, _ = np.histogramdd(reference, bins=self.bins, normed=False)
        self.flat_cube_s = H_ref / H_s
        self.flat_cube_b = H_b / H_ref
dataset/ETHPy150Open ml-slac/deep-jets/training/maxout-train-hypercube.py/NDWeights.fit/swapped operands of `/`