python: 绘制数学函数

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 100 linearly spaced numbers
 5 x = np.linspace(-5,5,100)
 6 
 7 # the function, which is y = x^2 here
 8 y = x**2
 9 
10 # setting the axes at the centre
11 fig = plt.figure()
12 ax = fig.add_subplot(1, 1, 1)
13 ax.spines['left'].set_position('center')
14 ax.spines['bottom'].set_position('zero')
15 ax.spines['right'].set_color('none')
16 ax.spines['top'].set_color('none')
17 ax.xaxis.set_ticks_position('bottom')
18 ax.yaxis.set_ticks_position('left')
19 
20 # plot the function
21 plt.plot(x,y, 'r')
22 
23 # show the plot
24 plt.show()

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 100 linearly spaced numbers
 5 x = np.linspace(-5,5,100)
 6 
 7 # the function, which is y = x^3 here
 8 y = x**3
 9 
10 # setting the axes at the centre
11 fig = plt.figure()
12 ax = fig.add_subplot(1, 1, 1)
13 ax.spines['left'].set_position('center')
14 ax.spines['bottom'].set_position('center')
15 ax.spines['right'].set_color('none')
16 ax.spines['top'].set_color('none')
17 ax.xaxis.set_ticks_position('bottom')
18 ax.yaxis.set_ticks_position('left')
19 
20 # plot the function
21 plt.plot(x,y, 'g')
22 
23 # show the plot
24 plt.show()

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 100 linearly spaced numbers
 5 x = np.linspace(-np.pi,np.pi,100)
 6 
 7 # the function, which is y = sin(x) here
 8 y = np.sin(x)
 9 
10 # setting the axes at the centre
11 fig = plt.figure()
12 ax = fig.add_subplot(1, 1, 1)
13 ax.spines['left'].set_position('center')
14 ax.spines['bottom'].set_position('center')
15 ax.spines['right'].set_color('none')
16 ax.spines['top'].set_color('none')
17 ax.xaxis.set_ticks_position('bottom')
18 ax.yaxis.set_ticks_position('left')
19 
20 # plot the function
21 plt.plot(x,y, 'b')
22 
23 # show the plot
24 plt.show()

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 100 linearly spaced numbers
 5 x = np.linspace(-np.pi,np.pi,100)
 6 
 7 # the function, which is y = sin(x) here
 8 y = np.sin(x)
 9 
10 # setting the axes at the centre
11 fig = plt.figure()
12 ax = fig.add_subplot(1, 1, 1)
13 ax.spines['left'].set_position('center')
14 ax.spines['bottom'].set_position('center')
15 ax.spines['right'].set_color('none')
16 ax.spines['top'].set_color('none')
17 ax.xaxis.set_ticks_position('bottom')
18 ax.yaxis.set_ticks_position('left')
19 
20 # plot the functions
21 plt.plot(x,y, 'b', label='y=sin(x)')
22 plt.plot(x,2*y, 'c', label='y=2sin(x)')
23 plt.plot(x,3*y, 'r', label='y=3sin(x)')
24 
25 plt.legend(loc='upper left')
26 
27 # show the plot
28 plt.show()

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 100 linearly spaced numbers
 5 x = np.linspace(-np.pi,np.pi,100)
 6 
 7 # the functions, which are y = sin(x) and z = cos(x) here
 8 y = np.sin(x)
 9 z = np.cos(x)
10 
11 # setting the axes at the centre
12 fig = plt.figure()
13 ax = fig.add_subplot(1, 1, 1)
14 ax.spines['left'].set_position('center')
15 ax.spines['bottom'].set_position('center')
16 ax.spines['right'].set_color('none')
17 ax.spines['top'].set_color('none')
18 ax.xaxis.set_ticks_position('bottom')
19 ax.yaxis.set_ticks_position('left')
20 
21 # plot the functions
22 plt.plot(x,y, 'c', label='y=sin(x)')
23 plt.plot(x,z, 'm', label='y=cos(x)')
24 
25 plt.legend(loc='upper left')
26 
27 # show the plot
28 plt.show()

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 100 linearly spaced numbers
 5 x = np.linspace(-2,2,100)
 6 
 7 # the function, which is y = e^x here
 8 y = np.exp(x)
 9 
10 # setting the axes at the centre
11 fig = plt.figure()
12 ax = fig.add_subplot(1, 1, 1)
13 ax.spines['left'].set_position('center')
14 ax.spines['bottom'].set_position('zero')
15 ax.spines['right'].set_color('none')
16 ax.spines['top'].set_color('none')
17 ax.xaxis.set_ticks_position('bottom')
18 ax.yaxis.set_ticks_position('left')
19 
20 # plot the function
21 plt.plot(x,y, 'y', label='y=e^x')
22 plt.legend(loc='upper left')
23 
24 # show the plot
25 plt.show()