.. 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_event_handling_ginput_manual_clabel_sgskip.py:
=====================
Interactive functions
=====================
This provides examples of uses of interactive functions, such as ginput,
waitforbuttonpress and manual clabel placement.
This script must be run interactively using a backend that has a
graphical user interface (for example, using GTK3Agg backend, but not
PS backend).
.. code-block:: default
import time
import numpy as np
import matplotlib.pyplot as plt
def tellme(s):
print(s)
plt.title(s, fontsize=16)
plt.draw()
Define a triangle by clicking three points
.. code-block:: default
plt.clf()
plt.setp(plt.gca(), autoscale_on=False)
tellme('You will define a triangle, click to begin')
plt.waitforbuttonpress()
while True:
pts = []
while len(pts) < 3:
tellme('Select 3 corners with mouse')
pts = np.asarray(plt.ginput(3, timeout=-1))
if len(pts) < 3:
tellme('Too few points, starting over')
time.sleep(1) # Wait a second
ph = plt.fill(pts[:, 0], pts[:, 1], 'r', lw=2)
tellme('Happy? Key click for yes, mouse click for no')
if plt.waitforbuttonpress():
break
# Get rid of fill
for p in ph:
p.remove()
Now contour according to distance from triangle
corners - just an example
.. code-block:: default
# Define a nice function of distance from individual pts
def f(x, y, pts):
z = np.zeros_like(x)
for p in pts:
z = z + 1/(np.sqrt((x - p[0])**2 + (y - p[1])**2))
return 1/z
X, Y = np.meshgrid(np.linspace(-1, 1, 51), np.linspace(-1, 1, 51))
Z = f(X, Y, pts)
CS = plt.contour(X, Y, Z, 20)
tellme('Use mouse to select contour label locations, middle button to finish')
CL = plt.clabel(CS, manual=True)
Now do a zoom
.. code-block:: default
tellme('Now do a nested zoom, click to begin')
plt.waitforbuttonpress()
while True:
tellme('Select two corners of zoom, middle mouse button to finish')
pts = plt.ginput(2, timeout=-1)
if len(pts) < 2:
break
(x0, y0), (x1, y1) = pts
xmin, xmax = sorted([x0, x1])
ymin, ymax = sorted([y0, y1])
plt.xlim(xmin, xmax)
plt.ylim(ymin, ymax)
tellme('All Done!')
plt.show()
.. _sphx_glr_download_gallery_event_handling_ginput_manual_clabel_sgskip.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: ginput_manual_clabel_sgskip.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: ginput_manual_clabel_sgskip.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
Keywords: matplotlib code example, codex, python plot, pyplot
`Gallery generated by Sphinx-Gallery
`_