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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Subject: Re: problem with Real_Matrix*Real_Matrix
Date: Mon, 17 Sep 2012 20:01:02 +0300
Date: 2012-09-17T20:01:02+03:00	[thread overview]
Message-ID: <abp3acF6d5tU1@mid.individual.net> (raw)
In-Reply-To: <cf82061e-ebae-46fc-b8d3-26c6dc9f84d9@googlegroups.com>

On 12-09-17 16:37 , reinkor wrote:
> Dear All,
> 
> I am confused about my result from the multiplication r*M where
> r is Real_Vector and M is Real_Matrix. Enclosed is my test program
> including comments.  Could someone look at it and maybe help me out
> of my bubble?
> 
> 
> I use gcc-ada-4.7-2.1.1.x86_64 under OpenSuse 12.2

I get the expected result:

** r*M :
  3010.0  4020.0

on my Mac, with GNAT 4.5.0 20100221 (experimental) [trunk revision 156937].

I suspect your Ada installation is broken, but I don't have any advice
on how to fix it, sorry.

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
      .      @       .


> 
> reinert
> 
> 
> with Text_IO;
> use  Text_IO;
> with   ada.numerics.Generic_Real_Arrays;
> 
> with Ada.Strings.Fixed;
> use  Ada.Strings,Ada.Strings.Fixed;
> 
> 
> procedure test3 is
> 
>   type Real is new Float;
> 
>   package Real_Io is new Text_IO.Float_Io   (Real);
>   use Real_Io;
> 
>   package Int_Io is new Text_IO.Integer_Io (Integer);
>   use Int_Io;
> 
>   package GRA is new Ada.Numerics.Generic_Real_Arrays(Real);
>   use GRA;
> 
>   procedure Put (X : Real_Vector) is
>   begin
>       for I in X'Range (1) loop
>           Put (X (I),6,1,0);
>       end loop;
>   end Put;
> 
>   M : Real_Matrix := ((1.0, 2.0),
>                       (3.0, 4.0));
> 
>   r : Real_Vector := (10.0,1000.0);
> 
> begin
> 
>    Put("** r*M : ");New_Line;
>    Put(r*M);
> 
> -- Extect: r*M = (10*1 + 1000*3, 10*2 + 1000*4) = (3010,4020)
> -- i.e. should r*M consists of the inner product between r and 
> -- the columns of M ?   But my program gives: 
> --
> -- ** r*M : 
> --     40.0  6000.0
> --      
> 
> end test3;
> 
> 




  reply	other threads:[~2012-09-21  1:13 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-17 13:37 problem with Real_Matrix*Real_Matrix reinkor
2012-09-17 17:01 ` Niklas Holsti [this message]
2012-09-18 10:18 ` Anatoly Chernyshev
2012-09-18 10:50   ` Simon Wright
2012-09-18 17:10     ` Anatoly Chernyshev
2012-09-18 18:16 ` Egil Høvik
2012-09-18 18:39   ` Anatoly Chernyshev
2012-09-18 19:23     ` Simon Wright
2012-09-18 20:33 ` AdaMagica
2012-09-19  6:11   ` reinkor
2012-09-19  8:17     ` Simon Wright
2012-09-19  8:55       ` Ken Thomas
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