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A **colorbar** is a bar that runs along the side of a Matplotlib chart and acts as a legend for the colors shown in the chart.

Matplotlib displays colorbars on the right side of a chart by default, but you can easily change this by using functions from the Matplotlib AxesGrid toolkit.

This tutorial shows several examples of how to use these functions in practice.

**Example 1: Position Colorbar on Right Side of Chart**

The following code shows how to generate a Matplotlib chart and how to place a colorbar on the right side of the chart:

import numpy as np import matplotlib.pyplot as plt from mpl_toolkits.axes_grid1 import make_axes_locatable #make this example reproducible np.random.seed(1) #create chart fig, ax = plt.subplots() im = ax.imshow(np.random.rand(15,15)) ax.set_xlabel('x-axis label') #add color bar fig.colorbar(im) plt.show()

**Example 2: Position Colorbar Below Chart**

The following code shows how to place a colorbar below a Matplotlib chart:

import numpy as np import matplotlib.pyplot as plt from mpl_toolkits.axes_grid1 import make_axes_locatable #make this example reproducible np.random.seed(1) #create chart fig, ax = plt.subplots() im = ax.imshow(np.random.rand(15,15)) ax.set_xlabel('x-axis label') #add color bar below chart divider = make_axes_locatable(ax) cax = divider.new_vertical(size='5%', pad=0.6, pack_start=True) fig.add_axes(cax) fig.colorbar(im, cax=cax, orientation='horizontal') plt.show()

Note that theÂ **padÂ **argument creates padding between the x-axis of the chart and the colorbar. The higher the value for pad, the further away the colorbar will be from the x-axis.

**Example 3: Position Colorbar Above Chart**

The following code shows how to place a colorbar above a Matplotlib chart:

import numpy as np import matplotlib.pyplot as plt from mpl_toolkits.axes_grid1 import make_axes_locatable #make this example reproducible np.random.seed(1) #create chart fig, ax = plt.subplots() im = ax.imshow(np.random.rand(15,15)) ax.set_xlabel('x-axis label') #add color bar below chart divider = make_axes_locatable(ax) cax = divider.new_vertical(size='5%', pad=0.4) fig.add_axes(cax) fig.colorbar(im, cax=cax, orientation='horizontal') plt.show()

*You can find more Matplotlib tutorials here.*