I want to insert rows to matrix with condition

i have this matrix

D=[ 1 2 3 4 0 0

    1 2 5 3 4 0
    1 3 1 0 0 0
    1 3 4 2 0 0
    2 1 6 0 0 0
    2 1 5 4 0 0
    2 3 4 2 0 0
    2 3 5 4 1 0
    3 1 2 0 0 0
    3 1 4 0 0 0 ]

i want to insert at each same raw ( same the 1&2 columns) for example

1 2 3 4 0 0

1 2 5 3 4 0

another raw (like 1&2 columns and 0 0 0 0)

1 2 0 0 0 0

for the matrix D become

D=[1 2 0 0 0 0

    1 2 3 4 0 0
    1 2 5 3 4 0
    1 3 0 0 0 0
    1 3 1 0 0 0
    1 3 4 2 0 0
    2 1 0 0 0 0
    2 1 6 0 0 0
    2 1 5 4 0 0
    2 3 0 0 0 0
    2 3 4 2 0 0
    2 3 5 4 1 0
    3 1 0 0 0 0
    3 1 2 0 0 0
    3 1 4 0 0 0 ]

[José-Luis]

Is this homework?

[mohammed sportman]

no this is part of my project

Answer 1

[José-Luis]

 your_mat = sortrows([a;b]);

Answer 2

[Image Analyst]

Hint: You can get a submatrix like this:

subMatrix = fullMatrix(1:someRow, :);
subMatrix = fullMatrix(row1:row2, :);
subMatrix = fullMatrix(someRow:end, :); % End has a special meaning

(pick one), and you can concatenate matrices vertically like this:

tallMatrix = [shortMatrix1; shortMatrix2]; % Use as many as you want

They all have to have the same number of columns of course.

[mohammed sportman]

sorry i can not understand

i have

a=[1 2 0 0 0

   1 3 0 0 0
   2 1 0 0 0
   3 1 0 0 0]

and

b=[1 2 1 0 0

   1 2 5 4 0 
   1 3 2 4 0 
   1 3 3 2 4 
   2 1 5 0 0 
   2 1 4 2 0 
   3 1 2 3 0 
   3 1 5 4 1 ]

i want to insert the first row of a to first row of b and second row of a to 3rd row of b .....etc like the result at question.

[Azzi Abdelmalek]

You gave a and b, what should be the result?

[Image Analyst]

What do you mean "to first row of b"? Do you mean insert that row of a "before" or "after" the first row of b, or do you mean that you want the row should overwrite ( not "insert") that row of b?