Indexing sections of arrays

Is there an easy way to extract every section's of n elements of a vector in MATLAB and skip the next n? Say we have

x = linspace(1,10,10); %[1 2 3 4 5 6 7 8 9 10]

I wish to index such that I grab 1,2,3 then skip 4,5,6 and again grab 7,8,9. For example,

a = zeros(1,10); % [0 0 0 0 0 0 0 0 0 0]

a(magic index) = x(magic index)

So now a = [1 2 3 0 0 0 7 8 9 0]

I've only been able to find how to get every nth element but not chunks of n elements.

Thank you for your help in advance !

[Jan w]

Define the indices you wish to extract

a = [1,2,3,7,8,9];

Now redefine your vector

x = x(a);

Is this what you mean?

[Mohammed Kagalwala]

Not exactly. I don't want a vector [1,2,3,7,8,9]. I want my 'a' vector to be [1 2 3 0 0 0 7 8 9 0]. Jos's answer below works as I wish !

Answer 1

[Jos (10584)]

x = 101:110
n = 3 
tf = mod(0:numel(x)-1, 2*n) < n
a = zeros(size(x)) 
a(tf) = x(tf)
index = find(tf)

[Mohammed Kagalwala]

Thank you ! Works perfectly :)