The following source code shows how to plot two mathematical functions (one linear and one quadratic) using the Matplotlib library, save the result to a PNG image, and display it on the screen. The functions are:
This is the resulting image:
And the code:

import matplotlib.pyplot as plt




# Quadratic function.


def f1(x):


return 2*(x**2) + 5*x  2




# Linear function.


def f2(x):


return 4*x + 1




# The X values to be plotted.


x = range(10, 15)




# Plot both functions.


# The second argument calculates the Y value for each of


# the X values defined above.


plt.plot(x, [f1(i) for i in x])


plt.plot(x, [f2(i) for i in x])




# Configure the color of the axes.


plt.axhline(0, color="black")


plt.axvline(0, color="black")




# The range of values shown by each axis.


plt.xlim(10, 10)


plt.ylim(10, 10)




# Save the plot as a PNG image.


plt.savefig("output.png")




# Show the result.


plt.show()

The Matplotlib library required by this code can be installed via python m pip install matplotlib
.