I have this python code.

1. it twinx the axis ax and plots some function on both axis
2. I plot the legend on ax1

The problem is that the legend is not covering the curves of ax2

It is possible to automatically positioning the legend on ax by covering the lines of ax2.

Note that in fig.legend the option loc="best" is not available. And I need the automatic positioning inside the area of the plot.

Tnx

import matplotlib.pyplot as plt
import numpy as np

# Set the x values for the sine and cosine functions
x = np.linspace(0, 2*np.pi, 100)

# Create the figure and an axis
fig, ax = plt.subplots()
ax2 = ax.twinx()

# Plot the sine and cosine functions on the axis
ax.plot(x, np.sin(x), label='Sine')
ax.plot(x, np.cos(x), label='Cosine')

ax2.plot(x, np.cos(x 1), label='Cosine 2', color="red")
ax2.plot(x, x, label='Cosine 2', color="green")

# Add a title and labels to the axis
ax.set_title('Sine and Cosine Functions')
ax.set_xlabel('X')
ax.set_ylabel('Y')

# Get the line legends from the axis
lines, labels = ax.get_legend_handles_labels()
lines2, labels2 = ax2.get_legend_handles_labels()

# Add a legend to the figure
ax.legend(lines   lines2, labels   labels2, framealpha=1.0)
ax.get_legend().set_zorder(10)

# Display the plot
plt.show()

Bellow is the output of the code:

CodePudding user response：

References:

CodePudding user response：

Thanks for the answer.

But my problem is more complex: I need to do this job in tiled subplots where every plot area is twinx.

By using the plt.label it seems to be impossible to select the plot-tile where to put the legend.

With the code below the problem is there. The lines of the twined are not covered by the legend.

Any suggestion?

import matplotlib.pyplot as plt
import numpy as np

# Set the x values for the sine and cosine functions
x = np.linspace(0, 2 * np.pi, 100)

# Create the figure and an axis
fig, ax = plt.subplots(2, 1)
ax2 = ax[0].twinx()
ax22 = ax[1].twinx()

# Plot the sine and cosine functions on the axis
ax[0].plot(x, np.sin(x), label='Sine 0')
ax[0].plot(x, np.cos(x), label='Cosine 0')

# Plot the sine and cosine functions on the axis
ax[1].plot(x, np.sin(x), label='Sine')
ax[1].plot(x, np.cos(x), label='Cosine')

ax2.plot(x, np.cos(x   1), label='Cosine 2', color="red")
ax2.plot(x, x, label='Cosine B', color="green")

ax22.plot(x, np.cos(x   2), label='Line 2', color="red")
ax22.plot(x, x, label='Cosine 2', color="green")

# Add a title and labels to the axis
ax[0].set_title('Sine and Cosine Functions')
ax[0].set_xlabel('X')
ax[0].set_ylabel('Y')

# Get the line legends from the axis
lines, labels = ax[0].get_legend_handles_labels()
lines2, labels2 = ax2.get_legend_handles_labels()

# Add a legend to the figure
ax[0].legend(lines   lines2, labels   labels2, framealpha=1.0, loc='lower right')


lines1, labels1 = ax[1].get_legend_handles_labels()
lines22, labels22 = ax22.get_legend_handles_labels()

# Add a legend to the figure
ax[1].legend(lines1   lines22, labels1   labels22, framealpha=1.0, loc='lower left')

# Display the plot
plt.show()

CodePudding user response：

With option 2 in my previous answer, I edited line 36 to ax2.legend(lines lines2, labels labels2, framealpha=1.0, loc='lower right') and line 43 to ax22.legend(lines1 lines22, labels1 labels22, framealpha=1.0, loc='lower left') in your newly provided code.

If you have multiple subfigures, using Axes objects are much more flexible.

It is now working correctly: