Two scales on one plot in Python
twinx shares the x axis and gives the second series its own y.
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
days = [1, 2, 3, 4, 5]
tpm = [88, 92, 99, 104, 110]
accuracy = [96.0, 97.2, 97.8, 98.4, 98.1]
figure, left = plt.subplots()
right = left.twinx()
left.plot(days, tpm, color="#7c5cff", marker="o")
right.plot(days, accuracy, color="#e06c75", linestyle="--")
left.set_ylabel("tpm", color="#7c5cff")
right.set_ylabel("accuracy %", color="#e06c75")
right.set_ylim(95, 100)
figure.savefig("twin.png")How it works
- Use it when the units genuinely differ, not to cram plots together.
- Color the tick labels to match their series.
- Two legends, or one combined from both handle lists.
Keywords and builtins used here
as
The run, in numbers
- Lines
- 19
- Characters to type
- 470
- Tokens
- 156
- Three-star pace
- 110 tpm
At the three-star pace of 110 tokens a minute, this run takes about 85 seconds.
Step 2 of 4 in Reading the plot, step 11 of 14 in Plotting with matplotlib.