Contour plots also called level plots are a tool for doing multivariate analysis and visualizing 3-D plots in 2-D space. If we consider X and Y as our variables we want to plot then the response Z will be plotted as slices on the X-Y plane due to which contours are sometimes referred as Z-slices or iso-response.
Contour plots are widely used to visualize density, altitudes or heights of the mountain as well as in the meteorological department. Due to such wide usage
matplotlib.pyplot provides a method
contour to make it easy for us to draw contour plots.
The matplotlib.pyplot.contour() are usually useful when Z = f(X, Y) i.e Z changes as a function of input X and Y. A
contourf() is also available which allows us to draw filled contours.
Syntax: matplotlib.pyplot.contour([X, Y, ] Z, [levels], **kwargs)
X, Y: 2-D numpy arrays with same shape as Z or 1-D arrays such that len(X)==M and len(Y)==N (where M and N are rows and columns of Z)
Z: The height values over which the contour is drawn. Shape is (M, N)
levels: Determines the number and positions of the contour lines / regions.
Below examples illustrate the
matplotlib.pyplot.contour() function in matplotlib.pyplot:
Example #1: Plotting of Contour using
contour() which only plots contour lines.
Example #2: Plotting of contour using
contourf() which plots filled contours.
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