时间:2022-06-26 10:33:42 | 栏目:Python代码 | 点击:次
这类方法是利用基本程序软件包numpy的随机数产生方法来生成各类用于聚类算法数据集合,也是自行制作轮子的生成方法。
from headm import * import numpy as np pltgif = PlotGIF() def moon2Data(datanum): x1 = linspace(-3, 3, datanum) noise = np.random.randn(datanum) * 0.15 y1 = -square(x1) / 3 + 4.5 + nois x2 = linspace(0, 6, datanum) noise = np.random.randn(datanum) * 0.15 y2 = square(x2 - 3) / 3 + 0.5 + noise plt.clf() plt.axis([-3.5, 6.5, -.5, 5.5]) plt.scatter(x1, y1, s=10) plt.scatter(x2, y2, s=10) plt.draw() plt.pause(.1) pltgif.append(plt) for _ in range(20): moon2Data(300) pltgif.save(r'd:\temp\GIF1.GIF')
from headm import * import numpy as np pltgif = PlotGIF() def moon2Data(datanum): x = np.random.rand(datanum, 2) condition1 = x[:, 1] <= x[:, 0] condition2 = x[:, 1] <= (1-x[:, 0]) index1 = np.where(condition1 & condition2) x1 = x[index1] x = np.delete(x, index1, axis=0) index2 = np.where(x[:, 0] <= 0.5) x2 = x[index2] x3 = np.delete(x, index2, axis=0) plt.clf() plt.scatter(x1[:, 0], x1[:, 1], s=10) plt.scatter(x2[:, 0], x2[:, 1], s=10) plt.scatter(x3[:, 0], x3[:, 1], s=10) plt.draw() plt.pause(.1) pltgif.append(plt) for _ in range(20): moon2Data(1000) pltgif.save(r'd:\temp\GIF1.GIF')
from headm import * import numpy as np pltgif = PlotGIF() def randData(datanum): t = 1.5 * pi * (1+3*random.rand(1, datanum)) x = t * cos(t) y = t * sin(t) X = concatenate((x,y)) X += 0.7 * random.randn(2, datanum) X = X.T norm = plt.Normalize(y.min(), y.max()) plt.clf() plt.scatter(X[:, 0], X[:, 1], s=10, c=norm(X[:,0]), cmap='viridis') plt.axis([-20, 21, -20, 16]) plt.draw() plt.pause(.1) pltgif.append(plt) for _ in range(20): randData(1000) pltgif.save(r'd:\temp\GIF1.GIF')
下面的知识螺旋线,没有随机移动的点。
将随机幅值从原来的0.7增大到1.5,对应的数据集合为:
利用sklearn.datasets自带的样本生成器来生成相应的数据集合。
from headm import * from sklearn.datasets import make_blobs pltgif = PlotGIF() def randData(datanum): x1,y1 = make_blobs(n_samples=datanum, n_features=2, centers=3, random_state=random.randint(0, 1000)) plt.clf() plt.scatter(x1[:,0], x1[:, 1], c=y1, s=10) plt.draw() plt.pause(.1) pltgif.append(plt) for _ in range(20): randData(300) pltgif.save(r'd:\temp\gif1.gif')
绘制三簇点集合,也可以使用如下的语句:
plt.scatter(x1[y1==0][:,0], x1[y1==0][:,1], s=10) plt.scatter(x1[y1==1][:,0], x1[y1==1][:,1], s=10) plt.scatter(x1[y1==2][:,0], x1[y1==2][:,1], s=10)
生成代码,只要在前面的x1后面使用旋转矩阵。
transformation = [[0.60834549, -0.63667341], [-0.40887718, 0.85253229]] x1 = dot(x1, transformation)
其中转换矩阵的特征值与特征向量为:
from headm import * from sklearn.datasets import make_circles pltgif = PlotGIF() def randData(datanum): x1,y1 = make_circles(n_samples=datanum, noise=0.07, random_state=random.randint(0, 1000), factor=0.6) plt.clf() plt.scatter(x1[y1==0][:,0], x1[y1==0][:,1], s=10) plt.scatter(x1[y1==1][:,0], x1[y1==1][:,1], s=10) plt.axis([-1.2, 1.2, -1.2, 1.2]) plt.draw() plt.pause(.1) pltgif.append(plt) for _ in range(20): randData(1000) pltgif.save(r'd:\temp\gif1.gif')
from headm import * from sklearn.datasets import make_moons pltgif = PlotGIF() def randData(datanum): x1,y1 = make_moons(n_samples=datanum, noise=0.07, random_state=random.randint(0, 1000)) plt.clf() plt.scatter(x1[y1==0][:,0], x1[y1==0][:,1], s=10) plt.scatter(x1[y1==1][:,0], x1[y1==1][:,1], s=10) plt.axis([-1.5, 2.5, -1, 1.5]) plt.draw() plt.pause(.1) pltgif.append(plt) for _ in range(20): randData(1000) pltgif.save(r'd:\temp\gif1.gif')