Use Line2D to plot line in python

Question

I have the data:

x = [10,24,23,23,3]
y = [12,2,3,4,2]

I want to plot it using

matplotlib.lines.Line2D(xdata, ydata)

I use

import matplotlib.lines

matplotlib.lines.Line2D(x, y)

But how do I show the line?

Answer 1

You should add the line to a plot and then show it:

In [13]: import matplotlib.pyplot as plt

In [15]: from matplotlib.lines import Line2D      

In [16]: fig = plt.figure()

In [17]: ax = fig.add_subplot(111)

In [18]: x = [10,24,23,23,3]

In [19]: y = [12,2,3,4,2]

In [20]: line = Line2D(x, y)

In [21]: ax.add_line(line)
Out[21]: <matplotlib.lines.Line2D at 0x7f4c10732f60>

In [22]: ax.set_xlim(min(x), max(x))
Out[22]: (3, 24)

In [23]: ax.set_ylim(min(y), max(y))
Out[23]: (2, 12)

In [24]: plt.show()

The result:

Answer 2

I have run into this problem when trying to replicate a line on two different plots. (mentioned in a comment "cannot put single artist in more than one figure) So assuming you already have a Line2D object from some other source and need it on new plot, the best way to add it to your plot is with:

line = Line2D(x, y)
plt.plot(*line.get_data(), ...)

You can also get a lot of the line's properties from its other "get" methods, found here.