#coding=utf-8
import matplotlib.pyplot as plt
import numpy as np

'''设置坐标轴 注解Annotation
'''
x = np.linspace(-3, 3, 50)
y = 2*x + 1

plt.figure(num=1, figsize=(8, 5),)
# 实线
plt.plot(x, y,)
#虚线
# plt.scatter(x, y,)

ax = plt.gca()
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')
ax.spines['top'].set_color('none')
ax.xaxis.set_ticks_position('bottom')
ax.spines['bottom'].set_position(('data', 0))
ax.yaxis.set_ticks_position('left')
ax.spines['left'].set_position(('data', 0))

x0 = 1
y0 = 2*x0 + 1
plt.scatter(x0, y0,s=50,color = 'b')
plt.plot([x0,x0],[y0,0],'k--',lw=2.5)

# method1
plt.annotate(r'$2x+1=%s$' %y0,xy=(x0,y0),xycoords='data', xytext=(+30,-30),textcoords='offset points', fontsize=16, arrowprops=dict(arrowstyle='->',connectionstyle='arc3, rad=.2'))

#method2
###########
plt.text(-3.7,3, r'$This\ is\ the\ some\ text.\ \mu\ sigma_i\ \alpha_t$', 
	fontdict={'size':16,'color':'r'})

plt.show()
49c9aa550e8782bfd0a24e56f65a91ed017b332d
<mask token>

<mask token>
plt.figure(num=1, figsize=(8, 5))
plt.plot(x, y)
<mask token>
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')
ax.spines['top'].set_color('none')
ax.xaxis.set_ticks_position('bottom')
ax.spines['bottom'].set_position(('data', 0))
ax.yaxis.set_ticks_position('left')
ax.spines['left'].set_position(('data', 0))
<mask token>
plt.scatter(x0, y0, s=50, color='b')
plt.plot([x0, x0], [y0, 0], 'k--', lw=2.5)
plt.annotate('$2x+1=%s$' % y0, xy=(x0, y0), xycoords='data', xytext=(+30, -
    30), textcoords='offset points', fontsize=16, arrowprops=dict(
    arrowstyle='->', connectionstyle='arc3, rad=.2'))
plt.text(-3.7, 3,
    '$This\\ is\\ the\\ some\\ text.\\ \\mu\\ sigma_i\\ \\alpha_t$',
    fontdict={'size': 16, 'color': 'r'})
plt.show()

<mask token>
x = np.linspace(-3, 3, 50)
y = 2 * x + 1
plt.figure(num=1, figsize=(8, 5))
plt.plot(x, y)
ax = plt.gca()
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')
ax.spines['top'].set_color('none')
ax.xaxis.set_ticks_position('bottom')
ax.spines['bottom'].set_position(('data', 0))
ax.yaxis.set_ticks_position('left')
ax.spines['left'].set_position(('data', 0))
x0 = 1
y0 = 2 * x0 + 1
plt.scatter(x0, y0, s=50, color='b')
plt.plot([x0, x0], [y0, 0], 'k--', lw=2.5)
plt.annotate('$2x+1=%s$' % y0, xy=(x0, y0), xycoords='data', xytext=(+30, -
    30), textcoords='offset points', fontsize=16, arrowprops=dict(
    arrowstyle='->', connectionstyle='arc3, rad=.2'))
plt.text(-3.7, 3,
    '$This\\ is\\ the\\ some\\ text.\\ \\mu\\ sigma_i\\ \\alpha_t$',
    fontdict={'size': 16, 'color': 'r'})
plt.show()

import matplotlib.pyplot as plt
import numpy as np
<mask token>
x = np.linspace(-3, 3, 50)
y = 2 * x + 1
plt.figure(num=1, figsize=(8, 5))
plt.plot(x, y)
ax = plt.gca()
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')
ax.spines['top'].set_color('none')
ax.xaxis.set_ticks_position('bottom')
ax.spines['bottom'].set_position(('data', 0))
ax.yaxis.set_ticks_position('left')
ax.spines['left'].set_position(('data', 0))
x0 = 1
y0 = 2 * x0 + 1
plt.scatter(x0, y0, s=50, color='b')
plt.plot([x0, x0], [y0, 0], 'k--', lw=2.5)
plt.annotate('$2x+1=%s$' % y0, xy=(x0, y0), xycoords='data', xytext=(+30, -
    30), textcoords='offset points', fontsize=16, arrowprops=dict(
    arrowstyle='->', connectionstyle='arc3, rad=.2'))
plt.text(-3.7, 3,
    '$This\\ is\\ the\\ some\\ text.\\ \\mu\\ sigma_i\\ \\alpha_t$',
    fontdict={'size': 16, 'color': 'r'})
plt.show()

#coding=utf-8
import matplotlib.pyplot as plt
import numpy as np

'''设置坐标轴 注解Annotation
'''
x = np.linspace(-3, 3, 50)
y = 2*x + 1

plt.figure(num=1, figsize=(8, 5),)
# 实线
plt.plot(x, y,)
#虚线
# plt.scatter(x, y,)

ax = plt.gca()
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')
ax.spines['top'].set_color('none')
ax.xaxis.set_ticks_position('bottom')
ax.spines['bottom'].set_position(('data', 0))
ax.yaxis.set_ticks_position('left')
ax.spines['left'].set_position(('data', 0))

x0 = 1
y0 = 2*x0 + 1
plt.scatter(x0, y0,s=50,color = 'b')
plt.plot([x0,x0],[y0,0],'k--',lw=2.5)

# method1
plt.annotate(r'$2x+1=%s$' %y0,xy=(x0,y0),xycoords='data', xytext=(+30,-30),textcoords='offset points', fontsize=16, arrowprops=dict(arrowstyle='->',connectionstyle='arc3, rad=.2'))

#method2
###########
plt.text(-3.7,3, r'$This\ is\ the\ some\ text.\ \mu\ sigma_i\ \alpha_t$', 
	fontdict={'size':16,'color':'r'})

plt.show()