Graph point on straight line (number line) in Python

问题

Trying to figure out what's the best way to graph a point on a number line in python. Essentially trying to make something similar to the image below:

I've been trying to use Matplotlib to do this but can't seem to figure it out. Anyone know of a package or anything out there I can use?

回答1:

I don't know of a specific package for this but you could do something like this in Matplotlib using hlines, vlines and plot.

import matplotlib.pyplot as plt

# set up the figure
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.)

# draw a point on the line
px = 4
plt.plot(px,y, 'ro', ms = 15, mfc = 'r')

# add an arrow
plt.annotate('Price five days ago', (px,y), xytext = (px - 1, y + 1), 
              arrowprops=dict(facecolor='black', shrink=0.1), 
              horizontalalignment='right')

# add numbers
plt.text(xmin - 0.1, y, '80', horizontalalignment='right')
plt.text(xmax + 0.1, y, '115', horizontalalignment='left')

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

回答2:

Here ya go, official example from matplotlib, including example code and everything. To plot a labeled point on the line, just do a normal scatterplot with the y coordinates being 0:

https://matplotlib.org/examples/ticks_and_spines/tick-locators.html

来源：https://stackoverflow.com/questions/23186804/graph-point-on-straight-line-number-line-in-python