Re: Any easy/build-in construct to extract submatrices from larger matrix?

["J-P. Rosen" <rosen@adalog.fr>]

Le 24/06/2012 19:14, Nasser M. Abbasi a �crit :

If you want to avoid "if" in "loop":

>> If you want a function which would return a submatrix obtained by
>> removing
>> the row I and column J:
> 
 function Exclude (A : Complex_Matrix; I, J : Integer)
     return Complex_Matrix is
     AI, AJ : Integer := A'First (1);
 begin
     return B : Complex_Matrix (1..A'Length (1)-1, 1..A'Length (2)-1) do
        BI := 1;
        for AI in A'First (1) .. I-1 loop
           BJ := 1;
           for AJ in A'First (2) .. J-1 loop
              B (BI, BJ) := A (AI, AJ);
              BJ := BJ + 1;
           end loop;

           for AJ in J+1 .. A'Last (2) loop
              B (BI, BJ) := A (AI, AJ);
              BJ := BJ + 1;
           end loop;
           BI := BI + 1;
        end loop;

        for AI in I+1 .. A'Last (1) loop
           BJ := 1;
           for AJ in A'First (2) .. J-1 loop
              B (BI, BJ) := A (AI, AJ);
              BJ := BJ + 1;
           end loop;

           for AJ in J+1 .. A'Last (2) loop
              B (BI, BJ) := A (AI, AJ);
              BJ := BJ + 1;
           end loop;
           BI := BI + 1;
        end loop;
     end return;
 end Exclude;


-- 
J-P. Rosen
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