Plotting a Parametric Equation

Suppose that I need to plot B vs A.

A(T) = int (f(x),x,L1(x)>T),

B(T) = int (g(x),x,L2(x)<T),

How can I do it using matlab

Answer 1

[Walter Roberson]

L2(x)<T might be true for a whole series of non-contiguous x, so the meaning of your integration limits are not clear. Is the meaning that the integral is to be considered the sum of the integrals over each subregion (a, b) where a and b are successive zeros of L2(x)-T?

[Walter Roberson]

Suppose you have a function F(T) that returns whatever you mean by int(f(x), x, L1(x)>T) for that one given T. Likewise suppose G(T) that returns the relevant value for your second integral. Then

t=linspace(-20,15,50); %choose boundaries and number of points 
A = arrayfun(@F, t) ;
B = arrayfun(@G, t) ;
plot(A, B)