How can I copy one row to the another row?

I have an array like A below

A = [5 6 7 8 9 0 1 2 3 4;

5 6 7 8 9 0 1 2 3 4;

5 6 7 8 9 0 1 2 3 4;

5 6 7 8 9 0 1 2 3 4;

5 6 7 8 9 0 1 2 3 4]

I would like to do the following operaton :

every row shuld start from 0. So, for the first row discard all the values before 0 and append 5 6 7 8 9 from the next row and continue. Thus last row should have only

0 1 2 3 4 (padding rest of the position with 0). The new A should be like following

A = [ 0 1 2 3 4 5 6 7 8 9

0 1 2 3 4 5 6 7 8 9

0 1 2 3 4 5 6 7 8 9

0 1 2 3 4 0 0 0 0 0]

What is the efficinet way to do that? Thanks in advance.

[the cyclist]

How general is the example here? For example, ...

• Will the zeros always be aligned in a column?
• Could there be more than one columns of zeros?
• Could there be zeros scattered all around?
• Could there be more than one zero in a single row?

Please try to give a very general example of input and output.

[Sanjib Sarkar]

Each row should start with 0.

Each row corresponds to a each state and ecah state has 0 to 10 values.

Thus

row1 (state 1) should have 0 1 2 3 4 5 6 7 8 9

row2 (state2) should have 0 1 2 3 4 5 6 7 8 9

.

.

• Will the zeros always be aligned in a column? Yes
• Could there be more than one columns of zeros? No
• Could there be zeros scattered all around? NO
• Could there be more than one zero in a single row? No

Actually I have to cut and paste some values from the next row to the previous row.

Thanks!

Answer 1

[Jan]

A = [5 6 7 8 9 0 1 2 3 4;
     5 6 7 8 9 0 1 2 3 4;
     5 6 7 8 9 0 1 2 3 4;
     5 6 7 8 9 0 1 2 3 4;
     5 6 7 8 9 0 1 2 3 4];

% Find the first 0, transpose to row-wise operation:
At = A.';
k = find(At == 0, 1, 'first');

% Crop before 1st zero and pad with zeros:
B = [At(k:end), zeros(1, k-1)];

% Transpose and reshape B to the original size:
B = reshape(B, size(At)).'

[Sanjib Sarkar]

Thank you so much! It works.