Matplotlib is a library in Python and it is numerical – mathematical extension for NumPy library. The Axes Class contains most of the figure elements: Axis, Tick, Line2D, Text, Polygon, etc., and sets the coordinate system. And the instances of Axes supports callbacks through a callbacks attribute.
The Axes.clabel() function in axes module of matplotlib library is used to label a contour plot.
Syntax:
Axes.clabel(self, CS, *args, **kwargs)Parameters: This method accept the following parameters that are described below:
- cs : This parameter is the ContourSet to label.
- fontsize : This parameter is the size in points.
- gridsize : This parameter represents the number of hexagons in the x-direction or both direction.
- colors : This parameter is used to color the label
- inline : This parameter removes the underlying contour where the label is placed.
- inline_spacing : This parameter is space in pixels to leave on each side of label when placing inline.
- marginals : This parameter is used to plot the marginal density as colormapped rectangles along the bottom of the x-axis and left of the y-axis.
- fmt : This parameter is the format string for the label.
- manual : This parameter is used to place the contour label using mouse.
- rightside_up : This parameter is used to rotate the label.
- use_clabeltext : This parameter is used to create labels. ClabelText recalculates rotation angles of texts.
Returns: This returns the following:
- labels:This returns the list of Text instances for the labels.
Below examples illustrate the matplotlib.axes.Axes.clabel() function in matplotlib.axes:
Example-1:
# Implementation of matplotlib function import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
import matplotlib
delta = 2.5
x = np.arange( - 13.0 , 13.0 , delta)
y = np.arange( - 12.0 , 12.0 , delta)
X, Y = np.meshgrid(x, y)
Z = (np.exp( - X * * 2 - Y * * 2 ) - np.exp( - (X - 1 ) * * 2 - (Y - 1 ) * * 2 )) * 3
fig1, ax1 = plt.subplots()
CS1 = ax1.contour(X, Y, Z)
fmt = {}
strs = [ '1' , '2' , '3' , '4' , '5' , '6' , '7' ]
for l, s in zip (CS1.levels, strs):
fmt[l] = s
ax1.clabel(CS1, CS1.levels, inline = True ,
fmt = fmt, fontsize = 10 )
ax1.set_title( 'matplotlib.axes.Axes.clabel() Example' )
plt.show() |
Output:
Example-2:
# Implementation of matplotlib function import matplotlib
import numpy as np
import matplotlib.cm as cm
import matplotlib.pyplot as plt
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)
Z = (np.exp( - X * * 2 - Y * * 2 ) - np.exp( - (X - 1 ) * * 2 - (Y - 1 ) * * 2 )) * 3
fig, ax = plt.subplots()
im = ax.imshow(Z, interpolation = 'bilinear' , origin = 'lower' ,
cmap = "Greens", extent = ( - 3 , 3 , - 2 , 2 ))
levels = np.arange( - 1.2 , 1.6 , 0.2 )
CS = ax.contour(Z, levels, origin = 'lower' , cmap = 'spring' ,
linewidths = 2 , extent = ( - 3 , 3 , - 2 , 2 ))
zc = CS.collections[ 6 ]
plt.setp(zc, linewidth = 4 )
ax.clabel(CS, levels[ 1 :: 2 ], inline = 1 , fmt = '% 1.1f' ,
fontsize = 14 )
CB = fig.colorbar(CS, shrink = 0.8 , extend = 'both' )
CBI = fig.colorbar(im, orientation = 'horizontal' ,
shrink = 0.8 )
ax.set_title( 'matplotlib.axes.Axes.clabel() Example' )
plt.show() |
Output: