How to write a for loop with break condition... (reimann sum)

I am trying to create a for loop for a reimann sum with the condition that it will stop when the percent difference between iterations is <1%. Here is what I have so far...

x=9;
y=17;

L=10;
W=20;

sum=0;
sum2=0;
for n=1:2:inf
    p=(((-1)^(n+1)+1)/n)*sin((n*pi*x)/L)*((sinh((n*pi*y/L))/(sinh((n*pi*W/L)))));
    p2=(((-1)^(n+2)+1)/(n+1))*sin((n+1)*pi*x/L)*((sinh((n+1)*pi*y/L)/(sinh((n+1)*pi*W/L))));
    sum=sum+p;
    sum2=sum2+p2;
    if ((sum2-sum)/sum) < .01
        break
    else 
        continue
    end
end
sum*(2/pi)

[Walter Roberson]

Please do not name a variable "sum". "sum" is an important MATLAB routine to do addition, and you are quite likely to run into problems with confusing that routine with the variable. If not you then whoever reads your code is going to get confused.

Answer 1

[Azzi Abdelmalek]

Use while loop

sum=0;
sum2=0;
s1=1;
while s1>=0.01
  p=(((-1)^(n+1)+1)/n)*sin((n*pi*x)/L)*((sinh((n*pi*y/L))/(sinh((n*pi*W/L)))));
  p2=(((-1)^(n+2)+1)/(n+1))*sin((n+1)*pi*x/L)*((sinh((n+1)*pi*y/L)/(sinh((n+1)*pi*W/L))));
  sum=sum+p;
  sum2=sum2+p2;
  s1=(sum2-sum)/sum;
end