>>> """
=======================
Convert texts to images
=======================
"""
... 
... from io import BytesIO
... 
... from matplotlib.figure import Figure
... import matplotlib.pyplot as plt
... from matplotlib.transforms import IdentityTransform
... 
... 
... def text_to_rgba(s, *, dpi, **kwargs):
...     # To convert a text string to an image, we can:
...     # - draw it on an empty and transparent figure;
...     # - save the figure to a temporary buffer using ``bbox_inches="tight",
...     #   pad_inches=0`` which will pick the correct area to save;
...     # - load the buffer using ``plt.imread``.
...     #
...     # (If desired, one can also directly save the image to the filesystem.)
...     fig = Figure(facecolor="none")
...     fig.text(0, 0, s, **kwargs)
...     with BytesIO() as buf:
...         fig.savefig(buf, dpi=dpi, format="png", bbox_inches="tight",
...                     pad_inches=0)
...         buf.seek(0)
...         rgba = plt.imread(buf)
...     return rgba
... 
... 
... fig = plt.figure()
... rgba1 = text_to_rgba(r"IQ: $\sigma_i=15$", color="blue", fontsize=20, dpi=200)
... rgba2 = text_to_rgba(r"some other string", color="red", fontsize=20, dpi=200)
... # One can then draw such text images to a Figure using `.Figure.figimage`.
... fig.figimage(rgba1, 100, 50)
... fig.figimage(rgba2, 100, 150)
... 
... # One can also directly draw texts to a figure with positioning
... # in pixel coordinates by using `.Figure.text` together with
... # `.transforms.IdentityTransform`.
... fig.text(100, 250, r"IQ: $\sigma_i=15$", color="blue", fontsize=20,
...          transform=IdentityTransform())
... fig.text(100, 350, r"some other string", color="red", fontsize=20,
...          transform=IdentityTransform())
... 
... plt.show()
... 
... #############################################################################
... #
... # .. admonition:: References
... #
... #    The use of the following functions, methods, classes and modules is shown
... #    in this example:
... #
... #    - `matplotlib.figure.Figure.figimage`
... #    - `matplotlib.figure.Figure.text`
... #    - `matplotlib.transforms.IdentityTransform`
... #    - `matplotlib.image.imread`
...