I want to add number in given sequention

I want to add 0.5 to x2, x5, x8, x11 and so on, without altering the value of x1, x3, x4, x6, x7, x9, x10. How to write code for such problem.

Thank you

0.709416 x1

0.709416 x2

0.709416 x3

0.707508 x4

0.707508 x5

0.707508 x6

0.705603 x7

0.705603 x8

0.705603 x9

0.703701 x10

0.703701 x11

Answer 1

[Voss]

Referring to the code you posted in a comment:

v(2:3:end) = v(2:3:end)+0.05;

[Kundan Prasad]

Thank you. It worked

Answer 2

[KSSV]

You can extract indices using:

idx = 2:2:11 ;

[Kundan Prasad]

This is my code. I want to keep u value same as it is, but the value of v should be change according to the previous statement.

clc

clear all

z = -7.5:0.01:7.5;

r = 40;

x = r - sqrt(r.^2 - (z.^2));

u= repelem(z, 3);

v= repelem(x,3);

for i=2:3:4503

j(i)= v(i)+0.05;

end

[Rik]

I'm a bit confused about what you actually want to do. It sounds like KSSV's suggestion is exactly what you need:

v(2:2:end)=v(2:2:end)+0.5;