how can i resolve the "index in position 2 is invalid" error in line 99? the code works fine when N=15 but i need N=17.

clear
clc
tg=tfinal/(rept-1);
rt=(0:tg:tfinal);
rt(1)=1;
rt(rept)=tfinal;
for i=1:rept
ts(i)=rt(i)*dt; %times in seconds
end
ts(1)=0;
for j=1:rept
    for i=1:N
        ntd(i,1,:)=r(i);
        ntd(i,2,j)=T(i,rt(j));
    end   
end

Index in position 2 is invalid. Array indices must be positive integers or logical values.

Answer 1

[Walter Roberson]

timegap=tfinal/(rept-1);
rt=0:timegap:tfinal;
rt(1)=1;
rt(rept)=tfinal

Timegap is not certain to be an integer, so rt can contain non-integer values.

        ntd(i,2,j)=T(i,rt(j));

but you use rt as an index into T.

[mike roch]

how can i fix this?

[Walter Roberson]

rt = round(0:timegap:tfinal);

[mike roch]

Thank you!