int n_samples, n_features; n_samples = m_ldDatalen; if(m_bLastColumnisClassfication) { n_features = m_dFieldNum - 1; } else { n_features = m_dFieldNum; } n_features --; //特征数减1，最后一个为回归Y值 std::vector<std::vector<double>> X(n_samples, std::vector<double>(n_features)); std::vector<double> y(n_samples); for (int i = 0; i < n_samples; i++) { for (int j = 0; j < n_features; j++) { X[i][j] = g_fData[j*n_samples+i]; } y[i] = g_fData[n_features*n_samples+i]; } // 训练模型 //SGDRegression model(0.01, 1000, 1e-4); //model.fit(X, y); // 训练模型 ProbitRegression model(n_features); double learning_rate = 0.01; int num_iterations = 10000; model.fit(X, y, learning_rate, num_iterations);

这段代码看起来像是在对数据进行预处理和训练机器学习模型，可以看出数据的特征数和样本数分别由变量n_features和n_samples表示。然后通过双重循环，将原始数据中的特征值和回归Y值分别存入二维向量X和一维向量y中。

接下来，代码创建一个ProbitRegression类的对象model，并用fit()函数对数据进行训练。这里采用的是梯度下降的方式进行训练，其中学习率和训练次数在fit()函数中分别设置为learning_rate和num_iterations。

相关问题

翻译这段程序并自行赋值调用：import matplotlib.pyplot as plt import numpy as np import sklearn import sklearn.datasets import sklearn.linear_model def plot_decision_boundary(model, X, y): # Set min and max values and give it some padding x_min, x_max = X[0, :].min() - 1, X[0, :].max() + 1 y_min, y_max = X[1, :].min() - 1, X[1, :].max() + 1 h = 0.01 # Generate a grid of points with distance h between them xx, yy = np.meshgrid(np.arange(x_min, x_max, h), np.arange(y_min, y_max, h)) # Predict the function value for the whole grid Z = model(np.c_[xx.ravel(), yy.ravel()]) Z = Z.reshape(xx.shape) # Plot the contour and training examples plt.contourf(xx, yy, Z, cmap=plt.cm.Spectral) plt.ylabel('x2') plt.xlabel('x1') plt.scatter(X[0, :], X[1, :], c=y, cmap=plt.cm.Spectral) def sigmoid(x): s = 1/(1+np.exp(-x)) return s def load_planar_dataset(): np.random.seed(1) m = 400 # number of examples N = int(m/2) # number of points per class print(np.random.randn(N)) D = 2 # dimensionality X = np.zeros((m,D)) # data matrix where each row is a single example Y = np.zeros((m,1), dtype='uint8') # labels vector (0 for red, 1 for blue) a = 4 # maximum ray of the flower for j in range(2): ix = range(Nj,N(j+1)) t = np.linspace(j3.12,(j+1)3.12,N) + np.random.randn(N)0.2 # theta r = anp.sin(4t) + np.random.randn(N)0.2 # radius X[ix] = np.c_[rnp.sin(t), rnp.cos(t)] Y[ix] = j X = X.T Y = Y.T return X, Y def load_extra_datasets(): N = 200 noisy_circles = sklearn.datasets.make_circles(n_samples=N, factor=.5, noise=.3) noisy_moons = sklearn.datasets.make_moons(n_samples=N, noise=.2) blobs = sklearn.datasets.make_blobs(n_samples=N, random_state=5, n_features=2, centers=6) gaussian_quantiles = sklearn.datasets.make_gaussian_quantiles(mean=None, cov=0.5, n_samples=N, n_features=2, n_classes=2, shuffle=True, random_state=None) no_structure = np.random.rand(N, 2), np.random.rand(N, 2) return noisy_circles, noisy_moons, blobs, gaussian_quantiles, no_structure

这段程序是一个分类模型的辅助函数，包括了绘制决策边界、sigmoid函数和加载数据集的函数。具体实现如下：

import matplotlib.pyplot as plt
import numpy as np
import sklearn
import sklearn.datasets
import sklearn.linear_model

def plot_decision_boundary(model, X, y):
    # 设置最小值和最大值，并给它们一些填充
    x_min, x_max = X[0, :].min() - 1, X[0, :].max() + 1
    y_min, y_max = X[1, :].min() - 1, X[1, :].max() + 1
    h = 0.01

    # 生成一个网格，网格中点的距离为h
    xx, yy = np.meshgrid(np.arange(x_min, x_max, h), np.arange(y_min, y_max, h))

    # 对整个网格预测函数值
    Z = model(np.c_[xx.ravel(), yy.ravel()])
    Z = Z.reshape(xx.shape)

    # 绘制轮廓和训练样本
    plt.contourf(xx, yy, Z, cmap=plt.cm.Spectral)
    plt.ylabel('x2')
    plt.xlabel('x1')
    plt.scatter(X[0, :], X[1, :], c=y, cmap=plt.cm.Spectral)

def sigmoid(x):
    s = 1 / (1 + np.exp(-x))
    return s

def load_planar_dataset():
    np.random.seed(1)
    m = 400  # 样本数量
    N = int(m / 2)  # 每个类的样本数量

    # 生成数据集
    D = 2  # 特征维度
    X = np.zeros((m, D))  # 特征矩阵
    Y = np.zeros((m, 1), dtype='uint8')  # 标签向量

    a = 4  # 花的最大半径

    for j in range(2):
        ix = range(N*j, N*(j+1))
        t = np.linspace(j*3.12, (j+1)*3.12, N) + np.random.randn(N)*0.2  # theta
        r = a*np.sin(4*t) + np.random.randn(N)*0.2  # radius
        X[ix] = np.c_[r*np.sin(t), r*np.cos(t)]
        Y[ix] = j

    X = X.T
    Y = Y.T

    return X, Y

def load_extra_datasets():
    N = 200
    noisy_circles = sklearn.datasets.make_circles(n_samples=N, factor=.5, noise=.3)
    noisy_moons = sklearn.datasets.make_moons(n_samples=N, noise=.2)
    blobs = sklearn.datasets.make_blobs(n_samples=N, random_state=5, n_features=2, centers=6)
    gaussian_quantiles = sklearn.datasets.make_gaussian_quantiles(mean=None, cov=0.5, n_samples=N, n_features=2, n_classes=2, shuffle=True, random_state=None)
    no_structure = np.random.rand(N, 2), np.random.rand(N, 2)

    return noisy_circles, noisy_moons, blobs, gaussian_quantiles, no_structure

这段程序中包含了以下函数：

- `plot_decision_boundary(model, X, y)`：绘制分类模型的决策边界，其中`model`是分类模型，`X`是特征矩阵，`y`是标签向量。
- `sigmoid(x)`：实现sigmoid函数。
- `load_planar_dataset()`：加载一个二维的花瓣数据集。
- `load_extra_datasets()`：加载五个其他数据集。

class PointnetSAModuleMSG(_PointnetSAModuleBase): """ Pointnet set abstraction layer with multiscale grouping and attention mechanism """ def init(self, *, npoint: int, radii: List[float], nsamples: List[int], mlps: List[List[int]], bn: bool = True, use_xyz: bool = True, pool_method='max_pool', instance_norm=False): """ :param npoint: int :param radii: list of float, list of radii to group with :param nsamples: list of int, number of samples in each ball query :param mlps: list of list of int, spec of the pointnet before the global pooling for each scale :param bn: whether to use batchnorm :param use_xyz: :param pool_method: max_pool / avg_pool :param instance_norm: whether to use instance_norm """ super().init() assert len(radii) == len(nsamples) == len(mlps) self.npoint = npoint self.groupers = nn.ModuleList() self.mlps = nn.ModuleList() # Add attention module self.attentions = nn.ModuleList() for i in range(len(radii)): radius = radii[i] nsample = nsamples[i] self.groupers.append( pointnet2_utils.QueryAndGroup(radius, nsample, use_xyz=use_xyz) if npoint is not None else pointnet2_utils.GroupAll(use_xyz) ) mlp_spec = mlps[i] if use_xyz: mlp_spec[0] += 3 # Add attention module for each scale self.attentions.append(Attention(mlp_spec[-1])) self.mlps.append(pt_utils.SharedMLP(mlp_spec, bn=bn, instance_norm=instance_norm)) self.pool_method = pool_method def forward(self, xyz, features): """ :param xyz: (B, N, 3) xyz coordinates of the points :param features: (B, N, C) input features :return: (B, npoint, mlp[-1]) tensor """ new_features_list = [] for i in range(len(self.groupers)): grouper = self.groupers[i] mlp = self.mlps[i] attention = self.attentions[i] # Group points and features grouped_xyz, grouped_features = grouper(xyz, features) # Apply MLP to each group grouped_features = mlp(grouped_features) # Apply attention mechanism to the features of each group grouped_features = attention(grouped_features) # Perform pooling over each group if self.pool_method == 'max_pool': pooled_features = torch.max(grouped_features, dim=2)[0] else: pooled_features = torch.mean(grouped_features, dim=2) new_features_list.append(pooled_features) # Concatenate features from different scales new_features = torch.cat(new_features_list, dim=1) return new_features在该类中使用的QueryAndGroup类会主动将该类所继承的父类的返回值传入QueryAndGroup类中的forward函数吗

是的，该类中使用的QueryAndGroup类会调用其继承的父类_PointnetSAModuleBase的forward函数，并将其返回值传入QueryAndGroup类中的forward函数中。具体来说，QueryAndGroup类的forward函数接收点云数据和特征数据作为输入，然后调用父类_PointnetSAModuleBase的forward函数对点云数据进行处理，得到每个点所属的局部区域以及该区域内的点的特征，最后将点的坐标和特征数据传入MLP进行处理，得到该局部区域的特征表示。这些处理结果会被QueryAndGroup类返回供_PointnetSAModuleMSG类使用。