如何在Jupyter Notebook中永久修改matplotlib.rcParams默认值

Great question—having to re-set matplotlib rcParams every time you open Jupyter is such a hassle. Let's fix this for good with a few straightforward methods:

This method will apply your settings to every instance of matplotlib on your system, including Jupyter:

• First, find the path to the global config file. Run this in a Jupyter cell:

  import matplotlib
  print(matplotlib.matplotlib_fname())
  

• Open the file with a text editor (you might need admin/sudo privileges for system-level paths).
• Locate the parameters you want to change, remove the # comment, and replace the default value with your custom one. For example:

  # Original commented default
  # font.family:  sans-serif
  # Modified to your preference
  font.family:  'Arial'
  figure.dpi: 120
  axes.grid: True
  

• Save the file, restart Jupyter Notebook, and your settings will take effect automatically.

If you don't want to mess with system-wide settings, this is the safer option:

• Find your user-specific config directory by running this in Jupyter:

  import matplotlib
  print(matplotlib.get_configdir())
  

  The output will look like ~/.config/matplotlib (Linux/macOS) or C:\Users\YourUsername\.matplotlib (Windows).
• If there's no matplotlibrc file in this directory, create one.
• Add your custom parameters to the file (same format as the global config):

  # My personal matplotlib defaults
  font.family: 'Times New Roman'
  figure.dpi: 150
  axes.facecolor: #f5f5f5
  savefig.format: 'png'
  savefig.dpi: 300
  

• Save the file and restart Jupyter. These settings will load automatically and take priority over the global config.

If you want your settings to only apply to Jupyter (and not other Python environments using matplotlib):

• Find your Jupyter config directory by running this in a terminal/command prompt:

  jupyter --config-dir
  

• Create a custom/startup folder inside this directory if it doesn't exist.
• Make a new .py file in the startup folder (name it something like 00-matplotlib-defaults.py—the 00 ensures it runs first):

  import matplotlib.pyplot as plt
  
  # Set your preferred rcParams here
  plt.rcParams['font.family'] = 'Arial'
  plt.rcParams['figure.dpi'] = 120
  plt.rcParams['axes.grid'] = True
  plt.rcParams['axes.spines.right'] = False
  plt.rcParams['axes.spines.top'] = False
  

• Save the file, restart Jupyter, and your settings will be applied every time you open a notebook.

Quick Tips #

• You must restart Jupyter after modifying config files—refreshing the notebook page won't work.
• Priority order for settings: Jupyter startup script code > user-level matplotlibrc > global matplotlibrc.
• If you're unsure about a parameter name, run print(plt.rcParams) in Jupyter to see all available configs and their current values.

内容的提问来源于stack exchange，提问作者nonickname