utils.py 文件源码

def fit_transform(self, X, y=None):
        """Fit the model with X and apply the dimensionality reduction on X.
        Parameters
        ----------
        X : array-like, shape (n_samples, n_features)
            Training data, where n_samples is the number of samples
            and n_features is the number of features.
        Returns
        -------
        X_new : array-like, shape (n_samples, n_components)
        """
        U, S, V = self._fit(X)
        U = U[:, :int(self.n_components_)]

        if self.whiten:
            # X_new = X * V / S * sqrt(n_samples) = U * sqrt(n_samples)
            U *= sqrt(X.shape[0])
        else:
            # X_new = X * V = U * S * V^T * V = U * S
            U *= S[:int(self.n_components_)]

        return U