Position of the left nearest one value in a vector

3 views (last 30 days)
I have a vector of ones and zeros of this form: v = [0 0 1 0 0 0 1 1 1 1 0 0 1 1 0 0 0 0 0 1 0];
how can I get a vector with the left nearest zero from the one values, so that the output x is:
v = [0 0 1 0 0 0 1 1 1 1 0 0 1 1 1 0 0 1 0];
x = [0 0 2 0 0 0 6 6 6 6 0 0 12 12 12 0 0 17 0];
I am shamelly blocked so any hint to at least how to begin with would be very much appreciated.

Accepted Answer

madhan ravi
madhan ravi on 12 Sep 2019
Edited: madhan ravi on 12 Sep 2019
I don't know what you mean by shamely blocked.
It's not a trivial one though.
x=v;
Start=strfind([0,v==1],[0,1]);
End=strfind([v==1,0],[1,0]);
x(v==1)=repelem(Start-1,diff([Start;End+1]))

More Answers (2)

Bruno Luong
Bruno Luong on 12 Sep 2019
Edited: Bruno Luong on 13 Sep 2019
v = [0 0 1 0 0 0 1 1 1 1 0 0 1 1 1 0 0 1 0] % requirement: it must start with 0
Method 1
i0=find(v==0);
i1=find(v==1);
[~,loc]=histc(i1, [i0 Inf]);
v(i1)=i0(loc)
Method 2 (work with recent MATLAB versions)
i0=find(v==0);
i1=find(v==1);
v(i1)=interp1(i0,i0,i1,'previous')

Stephen23
Stephen23 on 13 Sep 2019
>> v = [0,0,1,0,0,0,1,1,1,1,0,0,1,1,1,0,0,1,0]
v =
0 0 1 0 0 0 1 1 1 1 0 0 1 1 1 0 0 1 0
>> d = diff([v,0])>0;
>> f = [0,find(d)];
>> x = f(1+v.*cumsum(d))
x =
0 0 2 0 0 0 6 6 6 6 0 0 12 12 12 0 0 17 0

Categories

Find more on Simscape Electrical in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!