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 GTKAgg backend, but not PS backend).
See also ginput_demo.py
Define a triangle by clicking three points
plt.clf()
plt.axis([-1., 1., -1., 1.])
plt.setp(plt.gca(), autoscale_on=False)
tellme('You will define a triangle, click to begin')
plt.waitforbuttonpress()
happy = False
while not happy:
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')
happy = plt.waitforbuttonpress()
# Get rid of fill
if not happy:
for p in ph:
p.remove()
Now contour according to distance from triangle corners - just an example
# 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
tellme('Now do a nested zoom, click to begin')
plt.waitforbuttonpress()
happy = False
while not happy:
tellme('Select two corners of zoom, middle mouse button to finish')
pts = np.asarray(plt.ginput(2, timeout=-1))
happy = len(pts) < 2
if happy:
break
pts = np.sort(pts, axis=0)
plt.axis(pts.T.ravel())
tellme('All Done!')
plt.show()
Total running time of the script: ( 0 minutes 0.000 seconds)