python课件-第17章 科学计算与可视化.ppt

17.3.2 绘制散点图 a = np.arange(0, 2.0*np.pi, 0.1) b = np.cos(a) pl.scatter(a,b) pl.show() 修改散点符号 a = np.arange(0, 2.0*np.pi, 0.1) b = np.cos(a) pl.scatter(a,b,marker=+) pl.show() 17.3.2 绘制散点图 17.3.2 绘制散点图 17.3.2 绘制散点图 import matplotlib.pylab as pl import numpy as np x = np.random.random(100) y = np.random.random(100) pl.scatter(x,y,s=x*500,c=ur,marker=u*) #s指大小，c指颜色，marker指符号形状 pl.show() 17.3.2 绘制散点图 17.3.3 绘制饼状图 import numpy as np import matplotlib.pyplot as plt #The slices will be ordered and plotted counter-clockwise. labels = Frogs, Hogs, Dogs, Logs sizes = [15, 30, 45, 10] colors = [yellowgreen, gold, #FF0000, lightcoral] explode = (0, 0.1, 0, 0.1) #使饼状图中第2片和第4片裂开 fig = plt.figure() ax = fig.gca() ax.pie(np.random.random(4), explode=explode, labels=labels, colors=colors, autopct=%1.1f%%, shadow=True, startangle=90, radius=0.25, center=(0, 0), frame=True) ax.pie(np.random.random(4), explode=explode, labels=labels, colors=colors, autopct=%1.1f%%, shadow=True, startangle=90, radius=0.25, center=(1, 1), frame=True) ax.pie(np.random.random(4), explode=explode, labels=labels, colors=colors, autopct=%1.1f%%, shadow=True, startangle=90, radius=0.25, center=(0, 1), frame=True) ax.pie(np.random.random(4), explode=explode, labels=labels, colors=colors, autopct=%1.1f%%, shadow=True, startangle=90, radius=0.25, center=(1, 0), frame=True) 17.3.3 绘制饼状图 ax.set_xticks([0, 1]) #设置坐标轴刻度 ax.set_yticks([0, 1]) ax.set_xticklabels([Sunny, Cloudy]) #设置坐标轴刻度上显示的标签 ax.set_yticklabels([Dry, Rainy]) ax.set_xlim((-0.5, 1.5)) #设置坐标轴跨度 ax.set_ylim((-0.5, 1.5)) ax.set_aspect(equal) #设置纵横比相等 plt.show() 17.3.3 绘制饼状图 17.3.3 绘制饼状图 17.3.4 使用pyplot绘制，多个图形在一起显示 import numpy as np import matplotlib.pyplot as plt x = np.linspace(0, 2*np.pi, 500) y = np.sin(x) z = np.cos(x*x) plt.figure(figsize=(8,4)) #标签前后加$将使用内嵌的LaTex引擎将其显示为