MATLAB - Remove Leading and Trailing Zeros From a Vector

matlab vector strip
nedblorf picture nedblorf · Mar 30, 2011 · Viewed 33.8k times · Source

I have a wavelet function with leading and trailing zeros. I would like to strip all the zeros which occur before or after the wavelet. However, I would not like to remove any zeros within the wavelet itself. To simplify, let's say I have the following 1x11 vector:

0 0 0 -2 -1 0 -1 -2 0 0 0

After removing leading and trailing zeros the vector should be:

-2 -1 0 -1 -2

My actual vectors are large and performance is my primary concern. I am a MATLAB novice and would appreciate any tips on how to accomplish this task as efficiently as possible.

Answer

Phonon picture Phonon · Mar 30, 2011

Try this

 y = x(find(x,1,'first'):find(x,1,'last'));

The find(x,1,'option') command gives you first and last non-zero indices.

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