PCA的Python代码
时间: 2023-11-05 16:52:26 浏览: 93
PCA的Python代码可以包括以下几个步骤:
1. 导入需要的包:
```python
import matplotlib.pyplot as plt
import matplotlib as mpl
from scipy.io import loadmat
from numpy import *
import pandas as pd
```
\[1\]
2. 导入数据集:
```python
def load_dataset():
path = './data/ex7data1.mat'
two_dimension_data = loadmat(path)
X = two_dimension_data\['X'\]
return X
```
\[2\]
3. 计算数据的协方差矩阵:
```python
def sigma_matrix(X_demean):
sigma = (X_demean.T @ X_demean) / X_demean.shape\[0\]
return sigma
```
\[3\]
以上是PCA的Python代码的基本框架,具体的PCA算法实现还需要根据具体需求进行进一步编写。
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