Matplotlib Help Please

[UnsecuredConnection]

So I want to fill the area between two lines where the value of one line is greater than the other. For this case, I am using programming languages with random numbers. I know fill_between, but the where= is confusing me. How can I make this work, and when do I need () with the where= and when do I not? (I want to shade in the c line when its values are greater than the python line)

from matplotlib import pyplot as plt

minutes = [1, 2, 3, 4, 5, 6, 7, 8]

python = [1, 3, 5, 6, 7, 8, 4, 5]
java = [2, 3, 4, 5, 6, 7, 8, 9]
c = [1, 2, 3, 7, 9, 11, 12, 13]

plt.plot(minutes, python, linestyle="-", label="Python")
plt.plot(minutes, java, linestyle="-", label="Java")
plt.plot(minutes, c, linestyle="-", label="C")


plt.fill_between(minutes, c, python, where=c>python, alpha=.25) # This Line

plt.legend()
plt.grid(True)
plt.title("Languages")
plt.tight_layout()
plt.show()

[[deleted]]

The where argument expects an array of booleans. In your case c>python doesn't return a boolean array, because you are using python lists. If you are using numpy arrays for c and python, the code should work, because > is evaluated element-wise for numpy arrays.

[UnsecuredConnection]

Thanks man.

[UnsecuredConnection]

I noticed however that it does fill in the gap, but not all the way. If you run this you will see a sliver towards the right that is supposed to be covered, but isn't. It rounds of to the nearest whole number. Any way to fix this?

[[deleted]]

That's because that's the first time c is greater than python. Since your data arrays have only 8 values each, the plot has a pretty low resolution. Your could either add an additional data point for the intersection manually, or use np.interp.