RK4 help (someone help fix this)

so i made the code but i only get the first two values then the values start to equal zeros wich shouldnt hapend.

this is the code :

x_start=0;    %valeeur initial de x 
x_end=1;    %valeur final de x
n_nodes=20;    
h=(x_end-x_start)/(n_nodes-1);
x=linspace(x_start, x_end, n_nodes);
y_RK4=zeros(1,n_nodes);
y_RK4(1)=3;
f=@(x,y) (-0.3*y+2*exp(-x));

for i=1,n_nodes-1; 
    k1=h*f(x(i),y_RK4(i));
    k2=h*f((x(i)+(h/2)),(y_RK4(i)+(k1/2)));
    k3=h*f((x(i)+(h/2)),(y_RK4(i)+(k2/2)));
    k4=h*f((x(i)+h),(y_RK4(i)+k3));
    y_RK4(i+1)=y_RK4(i)+(k1+(2*k2)+(2*k3)+k4)/6;
    
end

Answer 1

[Torsten]

Use

for i=1:n_nodes-1

instead of

for i=1,n_nodes-1;

[Aya]

MAN THANK YOU SM i was about to cry, its such a stupid mistake cus i didnt notice it since we had four difrent functions to plot. THANK YOU SO MUUUUCH AGAIN THANKS TO YOU I WONT CRY THIS NIGHT.

[Image Analyst]

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[Aya]

aha i did thanks man im new to matlab so i didnt know much :)))))