how to find Y value in a parametric plot without cursor

how do i find the value of Y at a specific X position, eg X=1

t= linspace (0,50,10000);
      X= (3*t)+ (1/sin(t))
      Y= -2*cos(t)

Answer 1

[Kian Azami]

To define the X matrix you need to put the "." before the "/" as below:

X= (3*t)+ (1./sin(t));

The Y is the function of t, so if you have the t you can find the value of Y easily.

But if you want to find a particular t so that X will have the value you want you can find the index of t first and then put that t inside the Y function and see the result. For example you want the X between 3 and 3.2, then you need to find the index of t that makes the X to be between 3 and 3.2. Then you put that t inside the Y and you find the value of Y.

idx = find(X >= 3 & X <= 3.2)
Y= -2*cos(t(idx));