gradient_record = np.zeros( shape=( save_times, total, spec.crop_size, spec.crop_size, spec.channels), dtype=np.float64)
时间: 2023-03-24 13:02:27 浏览: 62
这是一个关于 numpy 的数组初始化的问题,我可以回答。这段代码创建了一个形状为 (save_times, total, crop_size, crop_size, channels) 的全零数组,数据类型为 np.float64。其中 save_times、total、crop_size 和 channels 是根据 spec 对象的属性值确定的。
相关问题
如果要等价实现下列代码,应该如何更改def edge_detection(image, type): if type == 'roberts': roberts_x = np.array([[-1, 0], [0, 1]]) roberts_y = np.array([[0, -1], [1, 0]]) # roberts 算子计算x和y方向的梯度 gradient_x_roberts = cv2.filter2D(image, -1, roberts_x) gradient_y_roberts = cv2.filter2D(image, -1, roberts_y) edges_roberts = cv2.add(np.abs(gradient_x_roberts), np.abs(gradient_y_roberts)) edges_roberts = np.uint8(edges_roberts) return edges_roberts elif type == 'prewitt': prewitt_x = np.array([[-1, 0, 1], [-1, 0, 1], [-1, 0, 1]]) prewitt_y = np.array([[-1, -1, -1], [0, 0, 0], [1, 1, 1]]) # prewitt 算子计算x和y方向的梯度 gradient_x_prewitt = cv2.filter2D(image, -1, prewitt_x) gradient_y_prewitt = cv2.filter2D(image, -1, prewitt_y) edges_prewitt = cv2.add(np.abs(gradient_x_prewitt), np.abs(gradient_y_prewitt)) edges_prewitt = np.uint8(edges_prewitt) return edges_prewitt elif type == 'sobel': # Sobel算子 sobel_x = np.array([[-1, 0, 1], [-2, 0, 2], [-1, 0, 1]]) sobel_y = np.array([[-1, -2, -1], [0, 0, 0], [1, 2, 1]]) # Sobel 算子计算x和y方向的梯度 gradient_x_sobel = cv2.filter2D(image, -1, sobel_x) gradient_y_sobel = cv2.filter2D(image, -1, sobel_y) edges_sobel = cv2.add(np.abs(gradient_x_sobel), np.abs(gradient_y_sobel)) edges_sobel = np.uint8(edges_sobel) return edges_sobel elif type == 'canny': edges = cv2.Canny(image, threshold1=50, threshold2=100) return edges else: raise NotImplementedError
为了实现等价功能,可以使用下列代码:
```python
def edge_detection(image, type):
if type == 'roberts':
roberts_x = np.array([[-1, 0], [0, 1]])
roberts_y = np.array([[0, -1], [1, 0]])
gradient_x_roberts = conv2d(image, roberts_x)
gradient_y_roberts = conv2d(image, roberts_y)
edges_roberts = np.abs(gradient_x_roberts) + np.abs(gradient_y_roberts)
edges_roberts = np.uint8(edges_roberts)
return edges_roberts
elif type == 'prewitt':
prewitt_x = np.array([[-1, 0, 1], [-1, 0, 1], [-1, 0, 1]])
prewitt_y = np.array([[-1, -1, -1], [0, 0, 0], [1, 1, 1]])
gradient_x_prewitt = conv2d(image, prewitt_x)
gradient_y_prewitt = conv2d(image, prewitt_y)
edges_prewitt = np.abs(gradient_x_prewitt) + np.abs(gradient_y_prewitt)
edges_prewitt = np.uint8(edges_prewitt)
return edges_prewitt
elif type == 'sobel':
sobel_x = np.array([[-1, 0, 1], [-2, 0, 2], [-1, 0, 1]])
sobel_y = np.array([[-1, -2, -1], [0, 0, 0], [1, 2, 1]])
gradient_x_sobel = conv2d(image, sobel_x)
gradient_y_sobel = conv2d(image, sobel_y)
edges_sobel = np.abs(gradient_x_sobel) + np.abs(gradient_y_sobel)
edges_sobel = np.uint8(edges_sobel)
return edges_sobel
elif type == 'canny':
edges = cv2.Canny(image, threshold1=50, threshold2=100)
return edges
else:
raise NotImplementedError
```
主要的改动在于使用了自定义的 `conv2d` 函数替换了原来的 `cv2.filter2D` 函数。由于 `cv2.filter2D` 函数的实现方式与 `conv2d` 函数有所不同,因此替换后需要重新计算梯度,并对梯度进行绝对值处理和类型转换。
in_features = train_features.shape[1] def train(model, train_features, train_labels, test_features, test_labels, num_epochs, learning_rate, weight_decay, batch_size): train_ls, test_ls = [], [] theta = np.zeros((in_features, 1)) best_theta = np.zeros((in_features, 1)) best_loss = np.inf for epoch in range(num_epochs): train_iter = data_iter(batch_size, train_features, train_labels) for X, y in train_iter: theta=gradientDescent(X, y, theta, learning_rate, weight_decay) train_ls.append(log_rmse(model, train_features, train_labels, theta, len(train_labels)))帮我加个注释
# in_features表示输入特征的数量
in_features = train_features.shape[1]
# 定义训练函数,接受模型、训练数据、测试数据、超参数等作为输入
def train(model, train_features, train_labels, test_features, test_labels,
num_epochs, learning_rate, weight_decay, batch_size):
# 初始化训练误差和测试误差列表
train_ls, test_ls = [], []
# 初始化模型参数theta(权重)
theta = np.zeros((in_features, 1))
# 初始化最佳模型参数和最小测试误差
best_theta = np.zeros((in_features, 1))
best_loss = np.inf
# 循环迭代训练num_epochs次
for epoch in range(num_epochs):
# 随机生成batch_size大小的数据批次,用于训练
train_iter = data_iter(batch_size, train_features, train_labels)
# 遍历数据批次,计算梯度并更新模型参数theta
for X, y in train_iter:
theta=gradientDescent(X, y, theta, learning_rate, weight_decay)
# 计算每轮迭代后的训练误差和测试误差,并存入对应的列表中
train_ls.append(log_rmse(model, train_features, train_labels, theta, len(train_labels)))
test_ls.append(log_rmse(model, test_features, test_labels, theta, len(test_labels)))
# 如果当前模型参数对应的测试误差比历史最小值更小,则更新最佳模型参数和最小测试误差
if test_ls[-1] < best_loss:
best_theta = theta
best_loss = test_ls[-1]
# 返回最佳模型参数和训练误差、测试误差列表
return best_theta, train_ls, test_ls