how to shift arrays to the left

if i have

a=[0 0 0 0 0 0 0 0]

a(1,8)=5;

shifting a will results in :

a=[0 0 0 0 0 0 5 0]

how can i do that?

Answer 1

circshift(a,[0,-1])

If you always want the vacated edge of the matrix to be filled with zeros, you can use my noncircshift utility with the same syntax

function [B,src_indices,dest_indices]=noncircshift(A,offsets)
%Like circshift, but shifts are not circulant. Missing data are filled with
%zeros.
%
%  [B,src_indices,dest_indices]=noncirchift(A,offsets)
%
%B is the resulting array and the other outputs are such that
%
%  B(dest_indices{:})=A(src_indices{:})

siz=size(A);
N=length(siz);

if length(offsets)<N
   offsets(N)=0; 
end

B=zeros(siz);

indices=cell(3,N);

for ii=1:N

      for ss=[1,3]

       idx=(1:siz(ii))+(ss-2)*offsets(ii);

        idx(idx<1)=[];
        idx(idx>siz(ii))=[];

       indices{ss,ii}=idx;

      end
  end

src_indices=indices(1,:);
dest_indices=indices(3,:);

B(dest_indices{:})=A(src_indices{:});

thanx indeed