plt.lines code example

Example 1: matplotlib line plot

from matplotlib import pyplot as plt

# Median Developer Salaries by Age
dev_x = [25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35]

dev_y = [38496, 42000, 46752, 49320, 53200,
         56000, 62316, 64928, 67317, 68748, 73752]

plt.plot(dev_x, dev_y)
plt.xlabel('Ages')
plt.ylabel('Median Salary (USD)')
plt.title('Median Salary (USD) by Age')
plt.show()

#Basic line graph using python module matplotlib

Example 2: python matplotlib how to graph point on line

import matplotlib.pyplot as plt
fig = plt.figure()
ax = fig.add_subplot(111)
ax.set_xlim(0,10)
ax.set_ylim(0,10)

# draw lines
xmin = 1
xmax = 9
y = 5
height = 1
plt.hlines(y, xmin, xmax)
plt.vlines(xmin, y - height / 2., y + height / 2.)
plt.vlines(xmax, y - height / 2., y + height / 2.)
average = (xmax+xmin)/2

# draw a point on the line
px = 5 
plt.plot(px,y, 'ro', ms = 15, mfc = 'r')

# add an arrow
plt.annotate('Point', (px,y), xytext = (px+0.35, y+0.5), 
horizontalalignment='right')

# add numbers
plt.text(xmin - 0.1, y, 'Left', horizontalalignment='right')
plt.text(xmax + 0.1, y, 'Right', horizontalalignment='left')

plt.axis('off')
plt.show()