How do I refer to the next y point in a function?

say I have y = f(x), how can I refer to the next point in y(a+1) = f(x+1) with only using y in my code?

Thank you! :)

Answer 1

[KSSV]

You need to define x as an array, when you sustitue x in the function f, you will get output array y which is of same dimension like x. And after you can index.

EXamples:

f = @(x) sin(x) ; 
x = linspace(0,2*pi) ;
y = f(x) ;
plot(x,y)

for i = 1:10
    [x(i) y(i)]
end

ans = 1×2

0 0

ans = 1×2

0.0635 0.0634

ans = 1×2

0.1269 0.1266

ans = 1×2

0.1904 0.1893

ans = 1×2

0.2539 0.2511

ans = 1×2

0.3173 0.3120

ans = 1×2

0.3808 0.3717

ans = 1×2

0.4443 0.4298

ans = 1×2

0.5077 0.4862

ans = 1×2

0.5712 0.5406

If you are planning to use a loop (to learn).

f = @(x) sin(x) ; 
x = linspace(0,2*pi) ;
y = f(x) ;
n = length(x) ;
y = zeros(1,n) ;
for i = 1:n
    y(i)= f(x(i)) ; 
end
plot(x,y)