How can I remove the top and right axis in matplotlib?

[edit] matplotlib in now (2013-10) on version 1.3.0 which includes this

That ability was actually just added, and you need the Subversion version for it. You can see the example code here.

I am just updating to say that there’s a better example online now. Still need the Subversion version though, there hasn’t been a release with this yet.

[edit] Matplotlib 0.99.0 RC1 was just released, and includes this capability.

If you don’t need ticks and such (e.g. for plotting qualitative illustrations) you could also use this quick workaround:

Make the axis invisible (e.g. with plt.gca().axison = False) and then draw them manually with plt.arrow.

Alternatively, this

def simpleaxis(ax):
    ax.spines['top'].set_visible(False)
    ax.spines['right'].set_visible(False)
    ax.get_xaxis().tick_bottom()
    ax.get_yaxis().tick_left()

seems to achieve the same effect on an axis without losing rotated label support.

(Matplotlib 1.0.1; solution inspired by this).

_{(This is more of an extension comment, in addition to the comprehensive answers here.)}

Note that we can hide each of these three elements independently of each other:

• To hide the border (aka “spine”): ax.set_frame_on(False) or ax.spines['top'].set_visible(False)

• To hide the ticks: ax.tick_params(top=False)

• To hide the labels: ax.tick_params(labeltop=False)

Library Seaborn has this built in with function .despine().

Just add:

import seaborn as sns

Now create your graph. And add at the end:

sns.despine()

If you look at some of the default parameter values of the function it removes the top and right spine and keeps the bottom and left spine:

sns.despine(top=True, right=True, left=False, bottom=False)

Check out further documentation here:
https://seaborn.pydata.org/generated/seaborn.despine.html

If you need to remove it from all your plots, you can remove spines in style settings (style sheet or rcParams). E.g:

import matplotlib as mpl

mpl.rcParams['axes.spines.right'] = False
mpl.rcParams['axes.spines.top'] = False

If you want to remove all spines:

mpl.rcParams['axes.spines.left'] = False
mpl.rcParams['axes.spines.right'] = False
mpl.rcParams['axes.spines.top'] = False
mpl.rcParams['axes.spines.bottom'] = False

Another way of doing this in a non-global way is using the matplotlib.pyplot.rc_context context manager, as follows:

with plt.rc_context({
    "axes.spines.right": False,
    "axes.spines.top": False,
}):
    fig, ax = plt.subplots()
    ...

In case you want to apply this on a frequent basis, you can also create a style sheet as described here and use these settings:

axes.spines.left:   True
axes.spines.bottom: True
axes.spines.top:    False
axes.spines.right:  False

Although the accepted answer is good if all you want to do is turn off the axes lines, I would suggest getting familiar with the .set() function as you can pass additional kwargs controlling the line style, thickness, etc etc, making your code more flexible and re-usable. It also cuts down on the number of matplotlib functions you need to learn.

Op can do this:

ax.spines.top.set(visible=False)
ax.spines.right.set(visible=False)

but you can just as easily do something like this:

ax.spines.right.set(color='red', linestyle='--', linewidth=2, position=['data',2])
ax.spines.top.set(color='red', linestyle='--', linewidth=2, position=['data',5])

See documentation here.