Function to extract certain elements from a matrix

I have difficulties in making a function to extract columns after first number in the row from a the matrix. For example I have this matrix (A) and I want all columns that have first element 1 to be extracted in another matrix

A=   1 2 1 1 3
     2 5 6 4 8
     2 3 5 7 8

And I want my function to return this:

 B= 1 1 1
    2 6 4
    2 5 7

Answer 1

[Mischa Kim]

Ciuban, use

 B = A(:,A(1,:)==1)

[Sebastian Ciuban]

Awesome! Thank you very much

[Sebastian Ciuban]

It is possible to make a function, for example if I write extract(4) and in returns me all columns that have first element 4?

[Mischa Kim]

Sure

 function B = extr(A,extrnum)
 B = A(:,A(1,:)==extrnum);
 end