How to Properly Set Y-Axis Limits in Matplotlib?

Setting Axis Limits on Matplotlib

When dealing with data visualization using matplotlib, controlling the axis limits can be crucial to ensure that the data is presented optimally. This is particularly helpful when you want to zoom in on specific data ranges or highlight certain values.

In the context of matplotlib, setting the axis limits refers to specifying the minimum and maximum values for the x-axis and y-axis of a plot. As you encountered in your code, merely using the plt.ylim() function may not always produce the desired axis limits.

To address this issue effectively, you need to retrieve the current axis instance using plt.gca(). Once you have the axis instance represented by the ax variable, you can use the ax.set_ylim() method to set the specific limits you want.

For example, let's consider the code you provided and modify it to address your requirement of setting the y-axis limits to 20 and 250:

import matplotlib.pyplot as plt

plt.figure(1, figsize=(8.5, 11))
plt.suptitle('plot title')
ax = []
aPlot = plt.subplot(321, axisbg='w', title="Year 1")
ax.append(aPlot)
plt.plot(paramValues, plotDataPrice[0], color='#340B8C', marker='o', ms=5, mfc='#EB1717')
plt.xticks(paramValues)
plt.ylabel('Average Price')
plt.xlabel('Mark-up')
plt.grid(True)

# Retrieve current axis instance
ax = plt.gca()

# Set specific y-axis limits
ax.set_ylim([20, 250])

With this modification, your plot will display the y-axis limits set to 20 and 250, providing you with the desired data presentation.

The above is the detailed content of How to Properly Set Y-Axis Limits in Matplotlib?. For more information, please follow other related articles on the PHP Chinese website!