gtime.forecasting.GAR¶
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class
gtime.forecasting.GAR(estimator, n_jobs: int = None)¶ Generalized Auto Regression model.
This model is a wrapper of
sklearn.multioutput.MultiOutputRegressorbut returns apd.DataFrame.Fit one model for each target variable contained in the
ymatrix.Parameters: - estimator : estimator object, required
The model used to make the predictions step by step. Regressor object such as derived from
RegressorMixin.- n_jobs : int, optional, default:
None The number of jobs to use for the parallelization.
Examples
>>> import numpy as np >>> import pandas as pd >>> from gtime.forecasting import GAR >>> from sklearn.ensemble import RandomForestRegressor >>> time_index = pd.date_range("2020-01-01", "2020-01-30") >>> X = pd.DataFrame(np.random.random((30, 5)), index=time_index) >>> y_columns = ["y_1", "y_2", "y_3"] >>> y = pd.DataFrame(np.random.random((30, 3)), index=time_index, columns=y_columns) >>> X_train, y_train = X[:20], y[:20] >>> X_test, y_test = X[20:], y[20:] >>> random_forest = RandomForestRegressor() >>> gar = GAR(estimator=random_forest) >>> gar.fit(X_train, y_train) >>> predictions = gar.predict(X_test) >>> predictions.shape (10, 3)
Methods
fit(self, X, y[, sample_weight])Fit the model. get_params(self[, deep])Get parameters for this estimator. partial_fit(self, X, y[, sample_weight])Incrementally fit the model to data. predict(self, X)For each row in X, make a prediction for each fitted model, from 1 tohorizon.score(self, X, y[, sample_weight])Returns the coefficient of determination R^2 of the prediction. set_params(self, \*\*params)Set the parameters of this estimator. -
__init__(self, estimator, n_jobs: int = None)¶ Initialize self. See help(type(self)) for accurate signature.
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fit(self, X: pandas.core.frame.DataFrame, y: pandas.core.frame.DataFrame, sample_weight=None)¶ Fit the model.
Train the models, one for each target variable in y.
Parameters: - X : pd.DataFrame, shape (n_samples, n_features), required.
The data.
- y : pd.DataFrame, shape (n_samples, horizon), required.
The matrix containing the target variables.
Returns: - self : object
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get_params(self, deep=True)¶ Get parameters for this estimator.
Parameters: - deep : bool, default=True
If True, will return the parameters for this estimator and contained subobjects that are estimators.
Returns: - params : mapping of string to any
Parameter names mapped to their values.
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partial_fit(self, X, y, sample_weight=None)¶ Incrementally fit the model to data. Fit a separate model for each output variable.
Parameters: - X : (sparse) array-like, shape (n_samples, n_features)
Data.
- y : (sparse) array-like, shape (n_samples, n_outputs)
Multi-output targets.
- sample_weight : array-like of shape (n_samples,), default=None
Sample weights. If None, then samples are equally weighted. Only supported if the underlying regressor supports sample weights.
Returns: - self : object
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predict(self, X: pandas.core.frame.DataFrame) → pandas.core.frame.DataFrame¶ For each row in
X, make a prediction for each fitted model, from 1 tohorizon.Parameters: - X : pd.DataFrame, shape (n_samples, n_features), required
The data.
Returns: - y_p_df : pd.DataFrame, shape (n_samples, horizon)
The predictions, one for each timestep in horizon.
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score(self, X, y, sample_weight=None)¶ Returns the coefficient of determination R^2 of the prediction.
The coefficient R^2 is defined as (1 - u/v), where u is the residual sum of squares ((y_true - y_pred) ** 2).sum() and v is the regression sum of squares ((y_true - y_true.mean()) ** 2).sum(). Best possible score is 1.0 and it can be negative (because the model can be arbitrarily worse). A constant model that always predicts the expected value of y, disregarding the input features, would get a R^2 score of 0.0.
Parameters: - X : array-like, shape (n_samples, n_features)
Test samples.
- y : array-like, shape (n_samples) or (n_samples, n_outputs)
True values for X.
- sample_weight : array-like, shape [n_samples], optional
Sample weights.
Returns: - score : float
R^2 of self.predict(X) wrt. y.
Notes
R^2 is calculated by weighting all the targets equally using multioutput=’uniform_average’.
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set_params(self, **params)¶ Set the parameters of this estimator.
The method works on simple estimators as well as on nested objects (such as pipelines). The latter have parameters of the form
<component>__<parameter>so that it’s possible to update each component of a nested object.Parameters: - **params : dict
Estimator parameters.
Returns: - self : object
Estimator instance.