Increase nonzero values without deleting zeros

I have a vector X.

X=[0 0 0 0 1 1 1 1 0 0 0 0 0 0 2 2 2 2 2 2 0 0 0 3 3 3 3 0 0 0 0 0 4 4 4]

I want to increase the values of the nonzero elements in vector X by 10 However, when I do this using the find function I end up just having a vector without the zeros.

Y=X((find(X~=0)))+10;
Y=[11 11 11 11 22 22 ... ]

Is there a way to do this without using a for loop?

[KSSV]

Where you want to place the non zeros numbers?

[monmatlab]

at their initial positions. I want to have the same vector , just with the nonzeros increased by ten

Answer 1

[David J. Mack]

Hey monmatlab, simply use logical indexing:

Y = X;
isNonzero = X~=0;
Y(isNonzero) = 10*Y(isNonzero);

or the more compact inplace replacement:

X(X~=0) = 10*X(X~=0);

Greetings, David

[Adam]

If this is what you actually want to do, with multiplication then you can just skip the logical part and use

X = X * 10

since multiplying by 0 is 0 anyway! I was under the impression you wanted to add 10, not multiply by it though.

[David J. Mack]

Ah true, the OP stated to increase it... but it's the same idea anyway. Just replace the * by a +.

Answer 2

[Adam]

X = ( X ~= 0 ) .* ( X + 10 );