using x vector input to find corresponding y value

I am trying to find the corresponding y values to a x vector, which is x=[-2:0.5:16.5], but my code is not giving me back a list of y values. It is just displaying that y =0

Here's my code:

function findingy = findingy(x)

if x>=0 && x<=2.5

y=2*x;

elseif x>=2.5 && x<=7

y=5;

elseif x>=7 && x<14.5

y = 9.6667-0.6667*x;

else y=0

end

Answer 1

[Torsten]

Three possible solutions:

x = [-2:0.5:16.5];
y = findingy1(x);
figure(1)
plot(x,y)

y = findingy2(x);
figure(2)
plot(x,y)

y = arrayfun(@(i)findingy3(x(i)),1:numel(x));
figure(3)
plot(x,y)

function y = findingy1(x)
  y = zeros(size(x));
  y(x>=0 & x<=2.5) = 2*x(x>=0 & x<=2.5);
  y(x>=2.5 & x<=7) = 5;
  y(x>=7 & x<14.5) = 9.6667-0.6667*x(x>=7 & x<14.5);
end

function Y = findingy2(X)
  Y = zeros(size(X));
  for i = 1:numel(X)
    x = X(i);
    if x>=0 && x<=2.5
      y=2*x;
    elseif x>=2.5 && x<=7
      y=5;
    elseif x>=7 && x<14.5
      y = 9.6667-0.6667*x;
    else 
      y=0;
    end
    Y(i) = y;
  end
end

function y = findingy3(x)
  if x>=0 && x<=2.5
    y=2*x;
  elseif x>=2.5 && x<=7
    y=5;
  elseif x>=7 && x<14.5
    y = 9.6667-0.6667*x;
  else 
    y = 0;
  end
end