Python中Matplotlib库怎么用

from pylab import *
n = 256
X = np.linspace(-np.pi,np.pi,n,endpoint=True)
Y = np.sin(2*X)
plt.axes([0.025,0.025,0.95,0.95])
plt.plot (X, Y+1, color='blue', alpha=1.00)
plt.fill_between(X,1,Y+1,color='b',alpha=.25)
plt.plot (X, Y-1, color='blue', alpha=1.00)
plt.fill_between(X,-1,Y-1,(Y-1)>-1,color='b',alpha=.25)
plt.fill_between(X,-1,Y-1,(Y-1)<-1,color='r',alpha=.25)
plt.xticks([])
plt.yticks([])
plt.show()

from pylab import *
n = 1024
X = np.random.normal(0,1,n)
Y = np.random.normal(0,1,n)
T=np.arctan2(Y,X)
plt.axes([0.025,0.025,0.95,0.95])
plt.scatter(X,Y,s=60,c=T,alpha=.5)
plt.xlim(-1.5,1.5)
plt.ylim(-1.5,1.5)
plt.xticks([])
plt.yticks([])
plt.show()

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)

plt.bar(X, +Y1, facecolor='#9999ff', edgecolor='white')
plt.bar(X, -Y2, facecolor='#ff9999', edgecolor='white')
for x,y in zip(X,Y1):
    plt.text(x, y+0.05, '%.2f' % y, ha='center', va= 'bottom')

for x1,y1 in zip(X,Y2):
    plt.text(x1, -y1-0.05, '%.2f' % y1, ha='center', va= 'top')

plt.xlim(-.5,n),plt.xticks([])
plt.ylim(-1.25,+1.25),plt.yticks([])
plt.show()

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)
plt.axes([0.025,0.025,0.95,0.95])
plt.contourf(X,Y,f(X,Y),8, alpha=.75, cmap=plt.cm.hot)
C = plt.contour(X, Y, f(X,Y), 8, colors='black', linewidth=.5)
plt.clabel(C,inline=1,fontsize=10)
plt.xticks([]),plt.yticks([])
plt.show()

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)
Z=f(X,Y)
plt.axes([0.025,0.025,0.95,0.95])
plt.imshow(Z,interpolation='bicubic',cmap='bone',origin='lower')
plt.colorbar(shrink=.92)
plt.xticks([]), plt.yticks([])

from mpl_toolkits.mplot3d import Axes3D
fig=plt.figure()
ax=Axes3D(fig)
x=np.arange(-4.0,4.0,0.25)
y=np.arange(-4.0,4.0,0.25)
X,Y=np.meshgrid(x,y)
Z=np.sin(np.sqrt(X**2+Y**2))
surf=ax.plot_surface(X,Y,Z,
 rstride=1,
 cstride=1,
 cmap=plt.get_cmap('rainbow'))
ax.contourf(X,Y,Z,zdir='z',offset=-2,cmap=plt.cm.hot)
ax.set_zlim(-2,2)
fig.colorbar(surf,shrink=0.5,aspect=8)