how to add a row to a matrix?

A=[1;2;3;4;5]

i wanna add 0 to n row..i tried A(n, :) = 0...but i get this A=[0;2;3;4;5] instead of A=[0;1;2;3;4;5]

what's the problem?

Answer 1

[KSSV]

Note that you want to append zero before to the first element of A. What you did is replace the first element of A with 0.

A=[1;2;3;4;5] ;
A = [0;A]

A = 6×1

0 1 2 3 4 5

[arian hoseini]

i think u didnt read my explanation accurately or maybe i didnt explain my problem well... what if i want to add 0 to speific row ....if n=2

add 0 to second row ...A=[1;0;2;3;4;5]

[KSSV]

You check the output you have shown. In the output you have appended zero. You shuld not say adding at specific position, what you are doing is inserting. The procedure is same.

A = [1;2;3;4;5]  

A = 5×1

1 2 3 4 5

n = 2 ; 
A = [A(1:n-1) ; 0 ; A(n:end)]

A = 6×1

1 0 2 3 4 5

[arian hoseini]

A=[1;2;3;4;5]

add rows 2 and 5 to A to create B=[1;0;2;3;4;0;5]

A_temp=A;

index_rows=[2;5]

for i=1:size(index_rows,1)

mat1=A_temp(1:index_rows(i)-1);

mat2=A_temp(index_rows(i):end);

A_temp=[mat1;0;mat2];

end

B=A_temp;

i found the solution