其他类型的图
接下来的内容是练习。请运用你学到的知识，从提供的代码开始，实现配图所示的效果。具体的答案可以点击配图下载。
普通图
| 1 2 3 4 5 6 7 8 9 | from pylab import * n = 256 X = np.linspace(-np.pi,np.pi,n,endpoint=True) Y = np.sin(2*X) plot (X, Y+1, color=’blue’, alpha=1.00) plot (X, Y-1, color=’blue’, alpha=1.00) show() |
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散点图
| 1 2 3 4 5 6 7 8 | from pylab import * n = 1024 X = np.random.normal(0,1,n) Y = np.random.normal(0,1,n) scatter(X,Y) show() |
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条形图
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | from pylab import * n = 12 X = np.arange(n) Y1 = (1-X/float(n)) * np.random.uniform(0.5,1.0,n) Y2 = (1-X/float(n)) * np.random.uniform(0.5,1.0,n) bar(X, +Y1, facecolor=’#9999ff’, edgecolor=’white’) bar(X, -Y2, facecolor=’#ff9999′, edgecolor=’white’) for x,y in zip(X,Y1): text(x+0.4, y+0.05, ‘%.2f’ % y, ha=’center’, va= ‘bottom’) ylim(-1.25,+1.25) show() |
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等高线图
| 1 2 3 4 5 6 7 8 9 10 11 12 | from pylab import * def f(x,y): return (1-x/2+x**5+y**3)*np.exp(-x**2-y**2) n = 256 x = np.linspace(-3,3,n) y = np.linspace(-3,3,n) X,Y = np.meshgrid(x,y) contourf(X, Y, f(X,Y), 8, alpha=.75, cmap=’jet’) C = contour(X, Y, f(X,Y), 8, colors=’black’, linewidth=.5) show() |
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灰度图（Imshow）
| 1 2 3 4 5 6 7 8 9 | from pylab import * def f(x,y): return (1-x/2+x**5+y**3)*np.exp(-x**2-y**2) n = 10 x = np.linspace(-3,3,4*n) y = np.linspace(-3,3,3*n) X,Y = np.meshgrid(x,y) imshow(f(X,Y)), show() |
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饼状图
| 1 2 3 4 5 | from pylab import * n = 20 Z = np.random.uniform(0,1,n) pie(Z), show() |
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量场图（Quiver Plots）
| 1 2 3 4 5 | from pylab import * n = 8 X,Y = np.mgrid[0:n,0:n] quiver(X,Y), show() |
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网格
| 1 2 3 4 5 6 7 8 9 | from pylab import * axes = gca() axes.set_xlim(0,4) axes.set_ylim(0,3) axes.set_xticklabels([]) axes.set_yticklabels([]) show() |
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多重网格
| 1 2 3 4 5 6 7 | from pylab import * subplot(2,2,1) subplot(2,2,3) subplot(2,2,4) show() |
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极轴图
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | from pylab import * axes([0,0,1,1]) N = 20 theta = np.arange(0.0, 2*np.pi, 2*np.pi/N) radii = 10*np.random.rand(N) width = np.pi/4*np.random.rand(N) bars = bar(theta, radii, width=width, bottom=0.0) for r,bar in zip(radii, bars): bar.set_facecolor( cm.jet(r/10.)) bar.set_alpha(0.5) show() |
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3D 图
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 | from pylab import * from mpl_toolkits.mplot3d import Axes3D fig = figure() ax = Axes3D(fig) X = np.arange(-4, 4, 0.25) Y = np.arange(-4, 4, 0.25) X, Y = np.meshgrid(X, Y) R = np.sqrt(X**2 + Y**2) Z = np.sin(R) ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap=’hot’) show() |
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手稿
