Turning my function into an infinite loop

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Faris Sulam on 4 Jan 2021
Commented: Faris Sulam on 4 Jan 2021
Hi guys,
I wanted to ask of you about this code. I made a Simpson's rule code that does work when i place in the variables but now i want to edit it so that instead of placing iterations as a variable, the function would continuously iterate until it reaches a certain accpetable error.
function [ s ] = Simpson13( f,a,b,M)
h=(b-a)/(2*M);
s1=0;
s2=0;
for k=1:M;
x=a+h*(2*k-1);
s1=s1+f(x);
end
for k=1:(M-1);
x=a+h*2*k;
s2=s2+f(x);
end
s=h*(f(a)+f(b)+4*s1+2*s2)/3;
disp(s)
end
My plan is to replace all of the M into 'inf' and then putting an error statement afterwards to stop the infinite loop
TolMax=0.01; %the acceptable error
TolCur= abs(s(k)-s(k-1))/(s(k)); %I assume this is how one would calculate the error of the current value with the previous
if TolCur < TolMax
break
end
But according to matlab, i cant do this. Can someone give me any pointers to do this?

Mischa Kim on 4 Jan 2021
Edited: Mischa Kim on 4 Jan 2021
Hi Faris, instead of a for loop use a while loop with a condition like
while abs(s_k - s_k1) > TolMax
end
Above the loop you need to assign values to s_k and s_k1 so that you enter the loop.
Faris Sulam on 4 Jan 2021
Ah ok, your idea is way better, thanks