ezcontour
(Not recommended) Contour plotter
ezcontour
is not recommended. Use fcontour
instead.
Description
ezcontour(
plots the
contour lines of f(x,y), where
f
)f
is a symbolic expression that represents a mathematical function of
two variables, such as x and y.
ezcontour
automatically adds a title and axis labels.
The function f is plotted over the default domain –2π < x < 2π, –2π < y < 2π. MATLAB® software 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(
plots f(x,y) over the specified
f
,domain
)domain
. 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(___,
plots f over the default domain using an
n
)n
-by-n
grid. The default value for
n
is 60.
Examples
Plot Contour Lines of Symbolic Expression
The following mathematical expression defines a function of two variables, x and y.
ezcontour
requires a sym
argument that expresses
this function using MATLAB syntax to represent exponents, natural logs, etc. This function is represented
by the symbolic expression
syms x y f = 3*(1-x)^2*exp(-(x^2)-(y+1)^2)... - 10*(x/5 - x^3 - y^5)*exp(-x^2-y^2)... - 1/3*exp(-(x+1)^2 - y^2);
For convenience, this expression is written on three lines.
Pass the sym
f
to ezcontour
along with a domain ranging from
-3
to 3
and specify a computational grid of
49-by-49.
ezcontour(f,[-3,3],49)
In this particular case, the title is too long to fit at the top of the graph so MATLAB abbreviates the title.
Input Arguments
Version History
Introduced before R2006a