# Change or update an existing variable at iteration intervals in an iteration loop

1 view (last 30 days)
Ayobami Meadows on 18 Dec 2021
Answered: Sargondjani on 18 Dec 2021
I need to update the variable t with this same initilization formula when the iteration gets to iteration 10, iteration 15, iteration 25 and iteration 40. I tried this way but no changes.
clc;clear;close all;
MaxIt=50;
P=3;
xmin = randi(10);
ymin = 100;
x = [150 300 350];
y = [500 700 850];
%% Initialize variable t
t=zeros(1,P);
for i=1:P
t(i)=sqrt((y(i)-ymin)+(x(i)-xmin));
end
%% Main loop
for it=1:MaxIt
F = t * pi * randi(10);
GetCost = F(1);
disp(['MaxIt' num2str(it) ': Get Cost =' num2str(Fanswer(it))]);
%<------ This is where my problem is--------->
% I need to calculate and update variable t again here after 10th,
% 15th, 25th and 40th iterations. I did it this way but didn't work.
if (it)==[10 15 25 40]
for i=1:P
t(i)=sqrt((y(i)-ymin)+(x(i)-xmin));
end
end
end

Sargondjani on 18 Dec 2021
it==[10 15 25 40]
gives a vector as output. You want a scalar either 0 or 1:
Use:
ismember(it,[10 15 25 40])

R2020a

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