knn的python代码
时间: 2023-06-03 14:02:11 浏览: 51
好的,关于KNN的Python代码,以下是简单的实现示例:
```python
# 导入必要的库
import numpy as np
import pandas as pd
# 加载数据集
dataset = pd.read_csv('data.csv')
# 分割训练集和测试集
from sklearn.model_selection import train_test_split
X_train, X_test, y_train, y_test = train_test_split(dataset.iloc[:, :-1], dataset.iloc[:, -1], test_size=0.33, random_state=42)
# 特征缩放和归一化
from sklearn.preprocessing import StandardScaler
scaler = StandardScaler()
X_train = scaler.fit_transform(X_train)
X_test = scaler.transform(X_test)
# KNN模型的实现
from sklearn.neighbors import KNeighborsClassifier
k = 3 # 自定义K值
knn = KNeighborsClassifier(n_neighbors=k)
knn.fit(X_train, y_train)
# 对测试集进行预测
y_pred = knn.predict(X_test)
print("预测结果:", y_pred)
```
注意:以上代码仅是示例代码,实际应用场景需要根据具体的数据集进行适当的调整和优化。