.. _api-line_with_text:

api example code: line_with_text.py
===================================



.. plot:: /home/tcaswell/source/p/matplotlib/doc/mpl_examples/api/line_with_text.py

::

    """
    =======================
    Artist within an artist
    =======================
    
    Show how to override basic methods so an artist can contain another
    artist.  In this case, the line contains a Text instance to label it.
    """
    import numpy as np
    import matplotlib.pyplot as plt
    import matplotlib.lines as lines
    import matplotlib.transforms as mtransforms
    import matplotlib.text as mtext
    
    
    class MyLine(lines.Line2D):
        def __init__(self, *args, **kwargs):
            # we'll update the position when the line data is set
            self.text = mtext.Text(0, 0, '')
            lines.Line2D.__init__(self, *args, **kwargs)
    
            # we can't access the label attr until *after* the line is
            # inited
            self.text.set_text(self.get_label())
    
        def set_figure(self, figure):
            self.text.set_figure(figure)
            lines.Line2D.set_figure(self, figure)
    
        def set_axes(self, axes):
            self.text.set_axes(axes)
            lines.Line2D.set_axes(self, axes)
    
        def set_transform(self, transform):
            # 2 pixel offset
            texttrans = transform + mtransforms.Affine2D().translate(2, 2)
            self.text.set_transform(texttrans)
            lines.Line2D.set_transform(self, transform)
    
        def set_data(self, x, y):
            if len(x):
                self.text.set_position((x[-1], y[-1]))
    
            lines.Line2D.set_data(self, x, y)
    
        def draw(self, renderer):
            # draw my label at the end of the line with 2 pixel offset
            lines.Line2D.draw(self, renderer)
            self.text.draw(renderer)
    
    
    fig, ax = plt.subplots()
    x, y = np.random.rand(2, 20)
    line = MyLine(x, y, mfc='red', ms=12, label='line label')
    #line.text.set_text('line label')
    line.text.set_color('red')
    line.text.set_fontsize(16)
    
    
    ax.add_line(line)
    
    
    plt.show()
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)