From: "John B. Matthews" <nospam@nospam.invalid>
Subject: Re: Interfacing Ada with C
Date: Thu, 05 Aug 2010 09:23:51 -0400
Date: 2010-08-05T09:23:51-04:00 [thread overview]
Message-ID: <nospam-9BA736.09235105082010@news.aioe.org> (raw)
In-Reply-To: b7f5edce-124d-4b91-82f2-e9793d39a3cf@x25g2000yqj.googlegroups.com
In article
<b7f5edce-124d-4b91-82f2-e9793d39a3cf@x25g2000yqj.googlegroups.com>,
Ada novice <posts@gmx.us> wrote:
> 2. a real orthogonal matrix. Such a matrix gives all eigenvalues of
> unit modulus. I tested the case from
> http://en.wikipedia.org/wiki/Orthogonal_matrix.
> In Matlab,
>
> eig([0, -0.8, -0.6; 0.8, -0.36, 0.48; 0.6, 0.48, -0.64])
>
> gives the eigenvalues as 0 + 1i, 0 - 1i and -1.
>
> Using your Ada code gives:
>
> -1.78814E-08 1.00000E+00
> -8.72890E-09 -1.00000E+00
> -1.00000E+00 0.00000E+00
>
>
> Does the Blas code work with Fortran double-precision? In the above,
> Matlab with double (15 digits precision). I don't see you using the
> type Long_Float in the Ada code. I don't know how many digits are
> being passed from the Fortran result to Ada. Maybe this is causing the
> discrepancy between the expected results (all eigenvalues of modulus
> one) and the output in Ada.
Using these declarations in test_extensions.adb:
subtype My_Float is Long_Float;
Input : constant Complex_Matrix
:= (((0.0, 0.0), (-0.8, 0.0), -0.6, 0.0)),
((0.8, 0.0), (-0.36, 0.0), (0.48, 0.0)),
((0.6, 0.0), (0.48, 0.0), (-0.64, 0.0)));
I get this result:
./test_extensions
0.00000000000000E+00 1.00000000000000E+00
-2.77555756156289E-17 -1.00000000000000E+00
-1.00000000000000E+00 0.00000000000000E+00
[...]
--
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>
next prev parent reply other threads:[~2010-08-05 13:23 UTC|newest]
Thread overview: 112+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-24 11:57 Interfacing Ada with C Ada novice
2010-07-24 12:08 ` Robert A Duff
2010-07-24 12:32 ` Ada novice
2010-07-24 14:52 ` Marco
2010-07-24 16:38 ` Simon Wright
2010-07-24 17:58 ` Ada novice
2010-07-25 8:29 ` Simon Wright
2010-07-25 12:21 ` Ada novice
2010-07-25 13:50 ` Dmitry A. Kazakov
2010-07-25 14:12 ` Ada novice
2010-07-25 14:17 ` Ada novice
2010-07-25 14:26 ` Simon Wright
2010-07-25 16:18 ` Ada novice
2010-07-25 17:06 ` Dmitry A. Kazakov
2010-07-25 17:42 ` Ada novice
[not found] ` <a5ba4513-ce2b-45d1-a5f4-ff1a7945b0b0@q12g2000yqj.googlegroups.com>
2010-07-25 18:26 ` Dmitry A. Kazakov
2010-07-25 18:52 ` Ada novice
2010-07-25 18:58 ` Dmitry A. Kazakov
2010-07-25 19:13 ` Ada novice
2010-07-25 19:19 ` Dmitry A. Kazakov
2010-07-25 19:28 ` Ada novice
2010-07-25 20:04 ` Dmitry A. Kazakov
2010-07-26 13:40 ` Ada novice
2010-07-26 14:52 ` Dmitry A. Kazakov
2010-07-26 17:14 ` Ada novice
[not found] ` <a2da2804-c19b-44cf-9855-834c602c4520@y11g2000yqm.googlegroups.com>
2010-07-26 17:32 ` Dmitry A. Kazakov
2010-07-26 17:50 ` Ada novice
2010-07-27 12:24 ` Peter Hermann
2010-07-27 19:01 ` Ada novice
2010-07-28 9:56 ` team-ada (was e: " Peter Hermann
2010-07-27 5:50 ` Ada novice
2010-07-27 7:27 ` Dmitry A. Kazakov
2010-07-27 7:43 ` Georg Bauhaus
2010-07-27 18:37 ` Ada novice
2010-07-27 18:40 ` Ada novice
2010-07-25 17:24 ` Simon Wright
2010-07-25 17:47 ` Simon Wright
2010-07-25 17:58 ` Ada novice
2010-07-25 23:21 ` Simon Wright
2010-07-26 1:24 ` John B. Matthews
2010-07-26 14:01 ` Ada novice
2010-07-26 15:46 ` sjw
[not found] ` <da987804-3948-4871-ab52-4a8e95f06d44@k39g2000yqb.googlegroups.com>
2010-07-26 19:46 ` Simon Wright
2010-07-26 20:39 ` Dmitry A. Kazakov
2010-07-27 5:46 ` Ada novice
2010-07-27 5:43 ` Ada novice
2010-07-27 17:33 ` Simon Wright
2010-07-27 18:34 ` Ada novice
2010-07-28 22:26 ` Simon Wright
2010-07-29 9:19 ` Ada novice
2010-07-29 19:14 ` Simon Wright
2010-07-29 20:25 ` Ada novice
2010-07-30 1:46 ` John B. Matthews
2010-07-30 9:09 ` sjw
2010-07-30 12:41 ` Ada novice
2010-07-30 15:13 ` John B. Matthews
2010-07-30 17:25 ` Ada novice
2010-07-30 19:41 ` John B. Matthews
2010-07-30 21:08 ` Ada novice
2010-07-30 22:19 ` Simon Wright
2010-07-31 12:19 ` Ada novice
2010-07-31 13:25 ` Simon Wright
2010-07-31 19:39 ` Ada novice
2010-07-31 21:02 ` Simon Wright
2010-08-01 9:36 ` Ada novice
2010-08-01 16:14 ` Simon Wright
2010-08-01 16:27 ` Ada novice
2010-08-01 17:33 ` Simon Wright
[not found] ` <997036dd-ca13-4cdf-8f88-9b47a9f83b2d@s9g2000yqd.googlegroups.com>
2010-07-31 13:08 ` Simon Wright
2010-07-31 13:17 ` Simon Wright
2010-07-30 15:10 ` John B. Matthews
2010-08-01 10:47 ` John B. Matthews
2010-08-01 17:08 ` Simon Wright
2010-08-02 1:08 ` John B. Matthews
2010-08-02 16:36 ` Simon Wright
2010-08-02 16:55 ` Ada novice
2010-08-05 9:14 ` Ada novice
2010-08-05 13:23 ` John B. Matthews [this message]
2010-08-05 13:57 ` sjw
2010-08-05 17:24 ` Ada novice
2010-08-05 17:59 ` Jeffrey Carter
2010-08-05 20:25 ` Simon Wright
2010-08-06 1:15 ` John B. Matthews
2010-08-06 9:11 ` Ada novice
2010-08-06 9:17 ` Ada novice
2010-08-06 8:04 ` Jacob Sparre Andersen
2010-08-06 8:42 ` Dmitry A. Kazakov
2010-08-06 9:26 ` Ada novice
2010-08-06 9:51 ` Dmitry A. Kazakov
2010-08-06 12:04 ` Ada novice
2010-08-06 16:49 ` Simon Wright
2010-08-06 17:27 ` Dmitry A. Kazakov
2010-08-06 18:15 ` Ada novice
2010-08-06 20:26 ` Simon Wright
2010-08-07 0:46 ` John B. Matthews
2010-08-07 7:59 ` Dmitry A. Kazakov
2010-08-07 9:09 ` Georg Bauhaus
2010-08-07 12:33 ` John B. Matthews
2010-08-06 9:49 ` Peter Hermann
2010-08-06 12:03 ` Ada novice
2010-08-07 4:07 ` Randy Brukardt
2010-08-07 8:10 ` Ada novice
2010-08-06 16:41 ` Simon Wright
2010-08-06 8:39 ` sjw
2010-07-24 16:44 ` Dmitry A. Kazakov
2010-07-24 18:04 ` Ada novice
2010-07-24 19:16 ` Dmitry A. Kazakov
2010-07-25 0:22 ` tmoran
-- strict thread matches above, loose matches on Subject: below --
2003-04-14 21:39 Paul Anderson
2003-04-14 23:05 ` tmoran
2003-04-16 2:56 ` Steve
2003-04-16 4:25 ` Steve
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