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1.7.1.1 Demonstration: Plotting Multiple Figures within a Figure
Window
Using the data obtained in the previous example, observe the difference in
the partition of the page in the following two sets of commands:

subplot(2,1,1)
plot(x,y1)
subplot(2,1,2)
plot(x,y2)

and

clf
subplot(1,2,1)
plot(x,y1)
subplot(1,2,2)
plot(x,y2)

1.7.2 More on Parametric Plots in 2-D
In the preceding subsection, we generated the x- and y-arrays by first writing
the x-variable as a linear function of a parameter, and then expressed the
dependent variable y as a function of that same parameter. What we did is
that, instead of thinking of a function as a relation between an independent
variable x and a dependent variable y, we thought of both x and y as being
dependent functions of a third independent parameter. This method of curve
representation, known as the parametric representation, is described by (x(t),
y(t)), where the parameter t varies over some finite domain (t min , t max ). Note,
however, that in the general case, unlike the examples in the previous chapter
subsection, the independent variable x need not be linear in the parameter,
nor is the process of parametrization unique.

Example 1.11
Plot the trigonometric circle.

Solution: Recalling that the x-coordinate of any point on the trigonometric
circle has the cosine as x-component and the sine as y-component, the gener-
ation of the trigonometric circle is immediate:

th=linspace(0,2*pi,101)
x=cos(th);
y=sin(th);

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