[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
This commit is contained in:
pre-commit-ci[bot] 2024-10-23 14:10:46 +00:00
parent b72320b402
commit d4fc2bf852

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@ -1,6 +1,7 @@
import numpy as np
import pandas as pd
class RidgeRegression:
def __init__(self, alpha=0.001, regularization_param=0.1, num_iterations=1000):
self.alpha = alpha
@ -8,49 +9,48 @@ class RidgeRegression:
self.num_iterations = num_iterations
self.theta = None
def feature_scaling(self, X):
mean = np.mean(X, axis=0)
std = np.std(X, axis=0)
# avoid division by zero for constant features (std = 0)
std[std == 0] = 1 # set std=1 for constant features to avoid NaN
X_scaled = (X - mean) / std
return X_scaled, mean, std
def fit(self, X, y):
X_scaled, mean, std = self.feature_scaling(X)
m, n = X_scaled.shape
self.theta = np.zeros(n) # initializing weights to zeros
for i in range(self.num_iterations):
predictions = X_scaled.dot(self.theta)
error = predictions - y
# computing gradient with L2 regularization
gradient = (X_scaled.T.dot(error) + self.regularization_param * self.theta) / m
self.theta -= self.alpha * gradient # updating weights
# computing gradient with L2 regularization
gradient = (
X_scaled.T.dot(error) + self.regularization_param * self.theta
) / m
self.theta -= self.alpha * gradient # updating weights
def predict(self, X):
X_scaled, _, _ = self.feature_scaling(X)
return X_scaled.dot(self.theta)
def compute_cost(self, X, y):
X_scaled, _, _ = self.feature_scaling(X)
X_scaled, _, _ = self.feature_scaling(X)
m = len(y)
predictions = X_scaled.dot(self.theta)
cost = (1 / (2 * m)) * np.sum((predictions - y) ** 2) + (self.regularization_param / (2 * m)) * np.sum(self.theta**2)
cost = (1 / (2 * m)) * np.sum((predictions - y) ** 2) + (
self.regularization_param / (2 * m)
) * np.sum(self.theta**2)
return cost
def mean_absolute_error(self, y_true, y_pred):
return np.mean(np.abs(y_true - y_pred))
# Example usage
if __name__ == "__main__":
@ -60,7 +60,7 @@ if __name__ == "__main__":
y = (y - np.mean(y)) / np.std(y)
# Add bias term (intercept) to the feature matrix
X = np.c_[np.ones(X.shape[0]), X]
X = np.c_[np.ones(X.shape[0]), X]
# initialize and train the Ridge Regression model
model = RidgeRegression(alpha=0.01, regularization_param=0.1, num_iterations=1000)
@ -72,4 +72,4 @@ if __name__ == "__main__":
# results
print("Optimized Weights:", model.theta)
print("Cost:", model.compute_cost(X, y))
print("Mean Absolute Error:", model.mean_absolute_error(y, predictions))
print("Mean Absolute Error:", model.mean_absolute_error(y, predictions))