对自己电脑的图片,逻辑回归进行三者交叉验证,每类物体的准确率和总的准确率。,总共三种图片牛,马,车各六十张分别记为牛,马,车文件,这三个文件又在用同一个文件test下,python代码怎么写,地址是"D:\大三上\python\test",完整代码是什么
时间: 2024-09-18 10:17:00 浏览: 30
在Python中,你可以使用scikit-learn库来进行逻辑回归模型的训练,并使用交叉验证评估模型性能。这里是一个简单的例子,假设你已经将图片数据预处理好了并保存在"D:\大三上\python\test"目录下,每个类别有60张图片。
```python
import os
import numpy as np
from sklearn.model_selection import StratifiedKFold
from sklearn.linear_model import LogisticRegression
from sklearn.metrics import accuracy_score
# 假设你有一个函数读取图像数据并将其转换为特征向量
def load_data(file_path):
# 实现这个函数,根据图片内容提取特征并加载标签
pass
# 载入数据
train_dir = "D:\大三上\python\test"
data_features = []
labels = []
for category in ['牛', '马', '车']:
img_files = [os.path.join(train_dir, category, f) for f in os.listdir(os.path.join(train_dir, category))]
features, labels_category = load_data(img_files)
data_features.append(features)
labels += [category] * len(labels_category)
# 合并所有类别数据
all_features = np.concatenate(data_features)
labels = np.array(labels)
# 使用StratifiedKFold进行三次交叉验证
kfold = StratifiedKFold(n_splits=3)
accuracies = []
for train_index, val_index in kfold.split(all_features, labels):
X_train, y_train = all_features[train_index], labels[train_index]
X_val, y_val = all_features[val_index], labels[val_index]
# 创建逻辑回归模型
model = LogisticRegression()
model.fit(X_train, y_train)
# 预测并计算准确率
y_pred = model.predict(X_val)
accuracy = accuracy_score(y_val, y_pred)
accuracies.append(accuracy)
# 总准确率
overall_accuracy = sum(accuracies) / len(accuracies)
print(f"每类物体的准确率:{accuracies}")
print(f"总准确率:{overall_accuracy}")
```
注意,你需要完成`load_data`函数,使其接受路径列表作为输入,读取图片、提取特征并返回对应的特征数组和类别标签。由于涉及图像识别的具体步骤可能因使用的库和技术而异,这部分需要自行根据实际技术栈来编写。
阅读全文