How to initialize a matrix of one column only?

["Nasser M. Abbasi" <nma@12000.org>]

So trivial, yet Ada is giving me hard time with this
because I am a newbie.

I am trying to call SGESV in Lapack

http://www.netlib.org/lapack/single/sgesv.f

One of the arguments must be a matrix (the 'B' argument there).

I want to pass it a one column matrix. (i.e. I can't use a
Vector, it must be a matrix, since this is what the Ada Lapack
binding requires).

But I can't get the syntax to simply initialize the required
matrix to be a one column matrix. I keep getting the error

    nested array aggregate expected

I am sure this is trivial, but after tried all the
combinations I can think of, and googling around, I
give up. It works with the B matrix is (1..N,1..N)
but not when I write it as (1..N,1..1) to make it one
column matrix.
  
Here is the code, I write

----------------------
with Interfaces.Fortran;
use  Interfaces.Fortran;
with lbase;
   ....
   N: Fortran_Integer := 3;
   B: labase.Fortran_Real_Matrix ( 1..N, 1..1  );
BEGIN
   B := ((9.0) ,    -- here is the problem
         (2.0) ,
         (-2.0));
   ....
--------------------------------------------

where the labase package simply introduces a type for
Fortran_Real_Matrix as follows

----------------------------
   type Fortran_Real_Matrix is array (Fortran_Integer range <>,
                                      Fortran_Integer range <>)
          of Real;
     pragma Convention (Fortran, Fortran_Real_Matrix);
--------------------


>gnatmake -I../ada  lap42.adb
gcc -c -I../ada lap42.adb
lap42.adb:35:16: nested array aggregate expected
lap42.adb:35:16: if single-component aggregate is intended, write e.g. (1 => ...)
gnatmake: "lap42.adb" compilation error
>

I tried B:=(1=>9.0,2=>2.03=>-2.0);
and B := ((9.0 ,2.0 , 3));
but non working.

What is the correct syntax to use?

thanks,
--Nasser