def fit(self, X, y=None):
        """Fit detector. y is ignored in unsupervised methods.

        Parameters
        ----------
        X : numpy array of shape (n_samples, n_features)
            The input samples. Note that `n_features` must equal 1.

        y : Ignored
            Not used, present for API consistency by convention.

        Returns
        -------
        self : object
            Fitted estimator.
        """
        X = check_array(X, ensure_2d=False, force_all_finite=False)
        _check_dim(X)
        self._set_n_classes(y)
        self.threshold_ = self.threshold
        self.median_ = None  # reset median after each call
        self.median_diff_ = None  # reset median_diff after each call
        self.decision_scores_ = self.decision_function(X)
        self._process_decision_scores()

        return self
Fit detector. y is ignored in unsupervised methods.

        Parameters
        ----------
        X : numpy array of shape (n_samples, n_features)
            The input samples. Note that `n_features` must equal 1.

        y : Ignored
            Not used, present for API consistency by convention.

        Returns
        -------
        self : object
            Fitted estimator.
        
pyod/models/mad.py