SMOTE处理后的数据集三维可视化代码实现,每一步骤都说明一下
时间: 2024-09-25 13:02:57 浏览: 24
SMOTE(Synthetic Minority Over-sampling Technique),是一种常用的过采样技术,用于解决分类问题中的不平衡数据。它通过生成合成样本的方式增加少数类的数据量,以便提高模型对少数类别的识别能力。以下是一个基本的Python(使用Scikit-Learn库)和Matplotlib进行SMOTE处理后的数据集三维可视化的步骤:
```python
# 导入必要的库
import numpy as np
import matplotlib.pyplot as plt
from sklearn.datasets import make_classification
from imblearn.over_sampling import SMOTE
# 创建一个简单的不平衡数据集
X, y = make_classification(n_samples=1000, n_features=3, n_informative=3,
n_redundant=0, weights=[0.95, 0.05],
random_state=42)
# 使用SMOTE进行过采样
smote = SMOTE(random_state=42)
X_resampled, y_resampled = smote.fit_resample(X, y)
# 将结果转换成numpy数组方便操作
X_resampled = np.array(X_resampled)
y_resampled = np.array(y_resampled)
# 对过采样的数据进行三维可视化
fig = plt.figure(figsize=(8, 6))
ax = fig.add_subplot(projection='3d')
# 绘制原始数据点(蓝色)
ax.scatter(X[y == 0, 0], X[y == 0, 1], X[y == 0, 2], label="Original Class 0", color="blue")
ax.scatter(X[y == 1, 0], X[y == 1, 1], X[y == 1, 2], label="Original Class 1", color="red")
# 绘制过采样后的数据点(绿色)
ax.scatter(X_resampled[y_resampled == 0, 0], X_resampled[y_resampled == 0, 1], X_resampled[y_resampled == 0, 2], label="Oversampled Class 0", color="green")
ax.scatter(X_resampled[y_resampled == 1, 0], X_resampled[y_resampled == 1, 1], X_resampled[y_resampled == 1, 2], label="Oversampled Class 1", color="orange")
# 添加标签和图例
ax.set_xlabel('Feature 1')
ax.set_ylabel('Feature 2')
ax.set_zlabel('Feature 3')
ax.legend()
plt.title("SMOTE Data Visualization (Before and After)")
plt.show()
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