|MATLAB Function Reference|
Easy to use contour plotter
ezcontour(f) plots the contour lines of f(x,y), where
f is a string that represents a mathematical function of two variables, such as x and y.
The function f is plotted over the default domain: -2 < x < 2, -2 < y < 2. MATLAB chooses the computational grid according to the amount of variation that occurs; if the function f is not defined (singular) for points on the grid, then these points are not plotted.
ezcontour(f,domain) plots f(x,y) over the specified
domain can be either a 4-by-1 vector [xmin, xmax, ymin, ymax] or a 2-by-1 vector [min, max] (where min < x < max, min < y < max).
If f is a function of the variables u and v (rather than x and y), then the domain endpoints umin, umax, vmin, and vmax are sorted alphabetically. Thus,
ezcontour('u^2 - v^3',[0,1],[3,6]) plots the contour lines for u2 - v3 over 0 < u < 1, 3 < v < 6.
ezcontour(...,n) plots f over the default domain using an
n grid. The default value for
n is 60.
ezcontour automatically adds a title and axis labels.
Array multiplication, division, and exponentiation are always implied in the expression you pass to
ezcontour. For example, the MATLAB syntax for a contour plot of the expression,
is written as:
x^2 is interpreted as
x.^2 in the string you pass to
The following mathematical expression defines a function of two variables, x and y.
ezcontour requires a string argument that expresses this function using MATLAB syntax to represent exponents, natural logs, etc. This function is represented by the string:
For convenience, this string is written on three lines and concatenated into one string using square brackets.
Pass the string variable
ezcontour along with a domain ranging from -3 to 3 and specify a computational grid of 49-by-49:
In this particular case, the title is too long to fit at the top of the graph so MATLAB abbreviates the string.
Contour Plots for related functions