.. _pylab_examples-contour_label_demo: pylab_examples example code: contour_label_demo.py ================================================== .. plot:: /home/tcaswell/source/p/matplotlib/doc/mpl_examples/pylab_examples/contour_label_demo.py :: #!/usr/bin/env python """ Illustrate some of the more advanced things that one can do with contour labels. See also contour_demo.py. """ import matplotlib import numpy as np import matplotlib.cm as cm import matplotlib.mlab as mlab import matplotlib.ticker as ticker import matplotlib.pyplot as plt matplotlib.rcParams['xtick.direction'] = 'out' matplotlib.rcParams['ytick.direction'] = 'out' ################################################## # Define our surface ################################################## delta = 0.025 x = np.arange(-3.0, 3.0, delta) y = np.arange(-2.0, 2.0, delta) X, Y = np.meshgrid(x, y) Z1 = mlab.bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0) Z2 = mlab.bivariate_normal(X, Y, 1.5, 0.5, 1, 1) # difference of Gaussians Z = 10.0 * (Z2 - Z1) ################################################## # Make contour labels using creative float classes # Follows suggestion of Manuel Metz ################################################## plt.figure() # Basic contour plot CS = plt.contour(X, Y, Z) # Define a class that forces representation of float to look a certain way # This remove trailing zero so '1.0' becomes '1' class nf(float): def __repr__(self): str = '%.1f' % (self.__float__(),) if str[-1] == '0': return '%.0f' % self.__float__() else: return '%.1f' % self.__float__() # Recast levels to new class CS.levels = [nf(val) for val in CS.levels] # Label levels with specially formatted floats if plt.rcParams["text.usetex"]: fmt = r'%r \%%' else: fmt = '%r %%' plt.clabel(CS, CS.levels, inline=True, fmt=fmt, fontsize=10) ################################################## # Label contours with arbitrary strings using a # dictionary ################################################## plt.figure() # Basic contour plot CS = plt.contour(X, Y, Z) fmt = {} strs = ['first', 'second', 'third', 'fourth', 'fifth', 'sixth', 'seventh'] for l, s in zip(CS.levels, strs): fmt[l] = s # Label every other level using strings plt.clabel(CS, CS.levels[::2], inline=True, fmt=fmt, fontsize=10) # Use a Formatter plt.figure() CS = plt.contour(X, Y, 100**Z, locator=plt.LogLocator()) fmt = ticker.LogFormatterMathtext() fmt.create_dummy_axis() plt.clabel(CS, CS.levels, fmt=fmt) plt.title("\$100^Z\$") plt.show() Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)