Work with Array

Hello Is there any function to elimiate automomatically member with negetive index? for example:

i=1:10 y(i)=x(i-2);

it's a simple example. could you please help me? thank you.

Answer 1

[Jacob Halbrooks]

Logical indexing can be a good way to remove or manipulate elements in an array. In your case, let's say you have an array of indices, some of which are invalid (i.e. less than 1):

ind = [1:10]-2

Create a new array of indices with only valid values:

validInd = ind(ind >= 1)

If you wanted to instead replace illegal index values with a number such as 1, you could do this:

 validInd = ind;
 validInd(validInd< 1) = 1

Answer 2

[PHAM]

maybe we can try for i=2:12 y(i+2) = x(i)

[Mohammad]

Thank you . i said it's a simple example but in real program i can't do that.

if you know any function that put zero for illegal index , for example return 0 for x(-1), please help me.