.. only:: html
.. note::
:class: sphx-glr-download-link-note
Click :ref:`here ` to download the full example code
.. rst-class:: sphx-glr-example-title
.. _sphx_glr_gallery_images_contours_and_fields_demo_bboximage.py:
==============
BboxImage Demo
==============
A `~matplotlib.image.BboxImage` can be used to position an image according to
a bounding box. This demo shows how to show an image inside a `.text.Text`'s
bounding box as well as how to manually create a bounding box for the image.
.. code-block:: default
import matplotlib.pyplot as plt
import numpy as np
from matplotlib.image import BboxImage
from matplotlib.transforms import Bbox, TransformedBbox
fig, (ax1, ax2) = plt.subplots(ncols=2)
# ----------------------------
# Create a BboxImage with Text
# ----------------------------
txt = ax1.text(0.5, 0.5, "test", size=30, ha="center", color="w")
kwargs = dict()
bbox_image = BboxImage(txt.get_window_extent,
norm=None,
origin=None,
clip_on=False,
**kwargs
)
a = np.arange(256).reshape(1, 256)/256.
bbox_image.set_data(a)
ax1.add_artist(bbox_image)
# ------------------------------------
# Create a BboxImage for each colormap
# ------------------------------------
a = np.linspace(0, 1, 256).reshape(1, -1)
a = np.vstack((a, a))
# List of all colormaps; skip reversed colormaps.
maps = sorted(m for m in plt.colormaps() if not m.endswith("_r"))
ncol = 2
nrow = len(maps)//ncol + 1
xpad_fraction = 0.3
dx = 1./(ncol + xpad_fraction*(ncol - 1))
ypad_fraction = 0.3
dy = 1./(nrow + ypad_fraction*(nrow - 1))
for i, m in enumerate(maps):
ix, iy = divmod(i, nrow)
bbox0 = Bbox.from_bounds(ix*dx*(1 + xpad_fraction),
1. - iy*dy*(1 + ypad_fraction) - dy,
dx, dy)
bbox = TransformedBbox(bbox0, ax2.transAxes)
bbox_image = BboxImage(bbox,
cmap=plt.get_cmap(m),
norm=None,
origin=None,
**kwargs
)
bbox_image.set_data(a)
ax2.add_artist(bbox_image)
plt.show()
.. image:: /gallery/images_contours_and_fields/images/sphx_glr_demo_bboximage_001.png
:alt: demo bboximage
:class: sphx-glr-single-img
------------
References
""""""""""
The use of the following functions, methods, classes and modules is shown
in this example:
.. code-block:: default
import matplotlib
matplotlib.image.BboxImage
matplotlib.transforms.Bbox
matplotlib.transforms.TransformedBbox
matplotlib.text.Text
.. _sphx_glr_download_gallery_images_contours_and_fields_demo_bboximage.py:
.. only :: html
.. container:: sphx-glr-footer
:class: sphx-glr-footer-example
.. container:: sphx-glr-download sphx-glr-download-python
:download:`Download Python source code: demo_bboximage.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: demo_bboximage.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
Keywords: matplotlib code example, codex, python plot, pyplot
`Gallery generated by Sphinx-Gallery
`_