Visualization in Python

Introduction to Python for Finance

Adina Howe

Instructor

Matplotlib: A visualization package

See more of the Matplotlib gallery by clicking this link.

matplotlib

matplotlib.pyplot - diverse plotting functions

import matplotlib.pyplot as plt

matplotlib.pyplot - diverse plotting functions

plt.plot()
- takes arguments that describe the data to be plotted
plt.show()
- displays plot to screen

Plotting with pyplot

import matplotlib.pyplot as plt
plt.plot(months, prices)
plt.show()

Plot result

Simple plot2

Red solid line

import matplotlib.pyplot as plt
plt.plot(months, prices, color = 'red')
plt.show()

Plot result

redline

Dashed line

import matplotlib.pyplot as plt
plt.plot(months, prices, color = 'red', linestyle = '--')
plt.show()

Plot result

dash

Colors and linestyles

	color
'green'	green
'red'	red
'cyan'	cyan
'blue'	blue

	linestyle
'-'	solid line
'--'	dashed line
'-.'	dashed dot line
':'	dotted

More documentation on colors and lines can be found here.

Adding Labels and Titles

import matplotlib.pyplot as plt
plt.plot(months, prices, color = 'red', linestyle = '--')

# Add labels
plt.xlabel('Months')
plt.ylabel('Consumer Price Indexes, $')
plt.title('Average Monthly Consumer Price Indexes')

# Show plot
plt.show()

Plot result

labeled_plot

Adding additional lines

import matplotlib.pyplot as plt
plt.plot(months, prices, color = 'red', linestyle = '--')

# adding an additional line
plt.plot(months, prices_new, color = 'green', linestyle = '--') 

plt.xlabel('Months')
plt.ylabel('Consumer Price Indexes, $')
plt.title('Average Monthly Consumer Price Indexes')
plt.show()

Plot result

twolines

Scatterplots

import matplotlib.pyplot as plt
plt.scatter(x = months, y = prices, color = 'red')
plt.show()

Scatterplot result

scatterplot

Let's practice!

Introduction to Python for Finance