Introduction to Scikit-Learn

Scikit-learn is a machine learning library for Python. It features various classification, regression, and clustering algorithms.

Installation

pip install scikit-learn

Classification Example

from sklearn.datasets import load_iris
from sklearn.model_selection import train_test_split
from sklearn.ensemble import RandomForestClassifier
from sklearn.metrics import accuracy_score

# Load dataset
iris = load_iris()
X, y = iris.data, iris.target

# Split data
X_train, X_test, y_train, y_test = train_test_split(
    X, y, test_size=0.3, random_state=42
)

# Train model
clf = RandomForestClassifier(n_estimators=100)
clf.fit(X_train, y_train)

# Predict and evaluate
y_pred = clf.predict(X_test)
accuracy = accuracy_score(y_test, y_pred)
print(f"Accuracy: {accuracy:.2f}")

Regression Example

from sklearn.linear_model import LinearRegression
import numpy as np

# Sample data
X = np.array([[1], [2], [3], [4], [5]])
y = np.array([2, 4, 6, 8, 10])

# Create and train model
model = LinearRegression()
model.fit(X, y)

# Make predictions
predictions = model.predict([[6], [7]])
print(predictions)  # [12, 14]