How to make an endless calculated matrix?

For example I have matrix A(3,2) = [2 3; 4 5; 6 7] and matrix B(3,1) = [A(1,1)+A(1,2); A(2,1)+A(2,2); A(3,1)+A(3,2)]

Now, maybe I want to add 2 more rows in matrix A and I want B calculate those element without me writing A(4,1)+A(4,2) etc, automatically. For matrix A of ,,n" rows and 2 columns I want to make a B matrix of ,,n" rows and 1 column, B depending on A. Is there some set of commands to make this possible?

EDIT: What I really need is to know how to build matrix B ,which depends on A, using functions.

For example, we got: -*matrix* A(3,2)*= [2 3; 4 5; 6 7] -a function to calculate: sqrt(A(1,1)+A(1,2))/2 -*matrix* B(3,1)= [Function(A(1,1),A(1,2)); Function(A(2,1),A(2,2)); Function(A(3,1),A(3,2))] Now how can I build matrix B regardless of rows that matrix A have, without my input for every row in matrix B *Note: English is not my first language and I may not be very explicit.

Thank you!

Answer 1

[Andrei Bobrov]

A =  [2 3; 4 5; 6 7];
B = sum(A,2);

A(end+1,:) = [4 9]
B(end+1,:) = sum(A(end+1,:),2);

ADD

fun = @(x)sqrt(sum(x,2))/2;
B= fun(A);

[Sebastian Ciuban]

Thank you, indeed in this case it really works. What I really need is to know how to build matrix B ,which depends on A, using functions.

For example, we got: -*matrix* A(3,2)*= [2 3; 4 5; 6 7] -a function to calculate: sqrt(A(1,1)+A(1,2))/2 -*matrix* B(3,1)= [Function(A(1,1),A(1,2)); Function(A(2,1),A(2,2)); Function(A(3,1),A(3,2))] Now how can I build matrix B regardless of rows that matrix A have, without my input for every row in matrix B