diff --git a/sklearn_questions.py b/sklearn_questions.py index fa02e0d..45f0c69 100644 --- a/sklearn_questions.py +++ b/sklearn_questions.py @@ -82,6 +82,12 @@ def fit(self, X, y): self : instance of KNearestNeighbors The current instance of the classifier """ + X, y = check_X_y(X, y) + self.X_train_ = X + self.y_train_ = y + check_classification_targets(y) + self.n_features_in_ = X.shape[1] + self.classes_ = np.unique(y) return self def predict(self, X): @@ -97,7 +103,16 @@ def predict(self, X): y : ndarray, shape (n_test_samples,) Predicted class labels for each test data sample. """ - y_pred = np.zeros(X.shape[0]) + check_is_fitted(self) + X = check_array(X) + y_pred = np.zeros(X.shape[0], dtype=self.y_train_.dtype) + dist = pairwise_distances(X, self.X_train_, metric='minkowski') + nearest_ind = np.argsort(dist, axis=1)[:, :self.n_neighbors] + nearest_lab = self.y_train_[nearest_ind] + for i, label in enumerate(nearest_lab): + unique_labels, counts = np.unique(label, return_counts=True) + y_pred[i] = unique_labels[np.argmax(counts)] + return y_pred def score(self, X, y): @@ -115,7 +130,12 @@ def score(self, X, y): score : float Accuracy of the model computed for the (X, y) pairs. """ - return 0. + check_is_fitted(self) + X, y = check_X_y(X, y) + y_pred = self.predict(X) + accuracy = np.mean(y_pred == y) + + return accuracy class MonthlySplit(BaseCrossValidator): @@ -155,9 +175,24 @@ def get_n_splits(self, X, y=None, groups=None): n_splits : int The number of splits. """ - return 0 - - def split(self, X, y, groups=None): + if not isinstance(X, type(pd.DataFrame())): + time_data = pd.DataFrame({'date': X.index, 'val': X.values}) + time_data['date'] = pd.to_datetime(time_data['date']) + elif self.time_col == 'index' and 'date' not in X.columns[0]: + time_data = X.reset_index().copy() + time_data = time_data.rename( + columns={'index': 'date'}, inplace=False) + else: + time_data = X.copy() + if 'date' not in time_data.columns[0]: + time_data = time_data.rename({self.time_col: 'date'}) + unique_months = pd.to_datetime( + time_data['date']).dt.strftime('%b-%Y').unique() + n_splits = len(unique_months) - 1 + + return n_splits + + def split(self, X, y=None, groups=None): """Generate indices to split data into training and test set. Parameters @@ -177,12 +212,36 @@ def split(self, X, y, groups=None): idx_test : ndarray The testing set indices for that split. """ - - n_samples = X.shape[0] - n_splits = self.get_n_splits(X, y, groups) + if self.time_col != 'index': + if not isinstance(X[self.time_col].iloc[0], + type(pd.Timestamp('now'))): + raise ValueError('Index must be of type datetime') + else: + if not isinstance(X.index[0], type(pd.Timestamp('now'))): + raise ValueError('Index must be of type datetime') + if not isinstance(X, type(pd.DataFrame())): + time_data = pd.DataFrame({'date': X.index, 'val': X.values}) + time_data['date'] = pd.to_datetime(time_data['date']) + elif self.time_col == 'index': + time_data = X.reset_index().copy() + time_data = time_data.rename(columns={'index': 'date'}) + else: + time_data = X.copy() + if 'date' not in time_data.columns[0]: + time_data = time_data.rename(columns={self.time_col: 'date'}, + inplace=False) + n_splits = self.get_n_splits(time_data, y, groups) + time_data['period'] = pd.to_datetime( + time_data['date']).dt.strftime('%b-%Y') + + periods = np.unique(np.sort(pd.to_datetime(time_data['period'], + format='%b-%Y'))) + time_data['period'] = pd.to_datetime( + time_data['period'], format='%b-%Y') + time_data = time_data.reset_index() for i in range(n_splits): - idx_train = range(n_samples) - idx_test = range(n_samples) - yield ( - idx_train, idx_test - ) + idx_train = list( + time_data[time_data['period'] == periods[i]].index) + idx_test = list( + time_data[time_data['period'] == periods[i + 1]].index) + yield (idx_train, idx_test)