y'=1-(y/x), y(2)=-1, change in x =0.5. Im supposed to use Euler method to solve this differential equation but I'm not getting the answer I want. I have the code but I'm not sure if I'm doing it right.

This is my input and output. Im not sure why im not getting f. Am I like using the wrong code. I also think my y outputs are wrong. Please help!

Equation y'=1-(y/x), y(2)=-1, change in x =0.5.

h = 0.5 % step size

x = 2:h:1.5; % the range of x

y = zeros(size(x));

y(2) = -1; % the initial y value

n = numel(y);

for i=2:n-2

f = 1-(y(i)/x(i)) % the equation

y(i+1) = y(i) + (h * f);

end

y

h =

0.5000

y =

0 -1

Answer 1

[KSSV]

Your x value is not correct: You need to check this line:

x = 2:h:1.5; % the range of x

In the above you need to make changes.

h = 0.05 % step size
x = 1.5:h:2; % the range of x
y = zeros(size(x));
y(1) = -1; % the initial y value
n = numel(y);
for i=2:n-2
  f = 1-(y(i)/x(i)) % the equation
  y(i+1) = y(i) + (h * f);
end

[KSSV]

You have to check the loop index...I think the loop index for y should be (i-1).

h = 0.05 % step size
x = 1.5:h:2; % the range of x
y = zeros(size(x));
y(1) = -1; % the initial y value
n = numel(y);
for i=2:n-2
  f = 1-(y(i-1)/x(i-1)) % the equation
  y(i) = y(i-1) + (h * f);
end

If not, there is no necessity of loop.

[Rose Ahmad]

Thank you for your help! I tried changing things but it still didnt work. But I was able to find another code and was able to fgure it out.