2-D and 3-D Plots
To create two-dimensional line plots, use the
plot function. For example, plot the sine function over a linearly spaced vector of values from 0 to :
x = linspace(0,2*pi); y = sin(x); plot(x,y)
You can label the axes and add a title.
xlabel("x") ylabel("sin(x)") title("Plot of the Sine Function")
By adding a third input argument to the
plot function, you can plot the same variables using a red dashed line.
"r--" is a line specification. Each specification can include characters for the line color, style, and marker. A marker is a symbol that appears at each plotted data point, such as a
*. For example, "
g:*" requests a dotted green line with
Notice that the titles and labels that you defined for the first plot are no longer in the current figure window. By default, MATLAB® clears the figure each time you call a plotting function, resetting the axes and other elements to prepare the new plot.
To add plots to an existing figure, use
hold on. Until you use
hold off or close the window, all plots appear in the current figure window.
x = linspace(0,2*pi); y = sin(x); plot(x,y) hold on y2 = cos(x); plot(x,y2,":") legend("sin","cos") hold off
Three-dimensional plots typically display a surface defined by a function in two variables, . For instance, calculate given row and column vectors
y with 20 points each in the range [-2,2].
x = linspace(-2,2,20); y = x'; z = x .* exp(-x.^2 - y.^2);
Then, create a surface plot.
surf function and its companion
mesh display surfaces in three dimensions.
surf displays both the connecting lines and the faces of the surface in color.
mesh produces wireframe surfaces that color only the connecting lines.
You can display multiple plots in different parts of the same window using either
tiledlayout function was introduced in R2019b and provides more control over labels and spacing than
subplot. For example, create a 2-by-2 layout within a figure window. Then, call
nexttile each time you want a plot to appear in the next region.
t = tiledlayout(2,2); title(t,"Trigonometric Functions") x = linspace(0,30); nexttile plot(x,sin(x)) title("Sine") nexttile plot(x,cos(x)) title("Cosine") nexttile plot(x,tan(x)) title("Tangent") nexttile plot(x,sec(x)) title("Secant")
If you are using a release earlier than R2019b, see