The codes of this case can be downloaded here

Matplotlib is a Python plot library which produces publication quality figures. This blog will introduce that how to plot and improve a figure.

Matplotlib is easy to install with Python tool pip

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python -mpip install -U pip
python -mpip install -U matplotlib

I suggest that you install Anaconda, Anaconda is a welcome Python data science platform, it includes many Python packages like Numpy, SciPy and Matplotlib.

The following parts of this blog will show you how to plot and improve a figure with Matplotlib step by step.

A simple case

Here is a simple case from the gallery of Matplotlib

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import numpy as np
import matplotlib.pyplot as plt


t = np.arange(0., 50., 1)

# red dashes, blue squares and green triangles
plt.plot(t, t, 'r--', t, 2*t, 'bs')
plt.show()

In my github repository Learn Python, the procedure is described that how to remove the axes and the white margin of an image object that ploted by pyplot?. Just use fig = plt.figure() to produce a figure, then save it with

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fig.savefig("pyplot.png", bbox_inches='tight', pad_inches = 0)

The following shows the produced figure.

This figure is well enough to put into a paper or other normal publications, because it has different markers, clear ticks and a wrap border. But it can be improved to make it perfect.

Improvement

Axis ticks

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ax.xaxis.set_major_locator(ticker.MultipleLocator(5.00))
ax.xaxis.set_minor_locator(ticker.MultipleLocator(1.00))

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ax = plt.subplot(111)

$rm TeX$ used format

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from matplotlib import rc
rc('font',**{'family':'sans-serif','sans-serif':['Helvetica']})
rc('text', usetex=True)

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# Add label
font = {'family': 'serif',
        'color':  'black',
        'size': 22}
plt.xlabel(r'$x$', fontdict=font)
plt.ylabel(r'$y$', fontdict=font)
ax.tick_params(labelsize=18, colors='black',left='on')

# Add legend
plt.legend(loc = 'upper left',
        labels = [r'$y=x$',r'$y=2cdotx'],
        fancybox = True,
        fontsize = 16)

Add grid

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ax.set_axisbelow(True) # Set grid below the figure border when the grid's color is not black.
plt.grid(which='both', linewidth=1, color='gray')