From help-request at octave dot org Sat Apr 15 16:12:05 2006 Subject: Re: chol? From: Joe Koski To: Marius Schamschula , Vic Norton CC: Octave Help Date: Sat, 15 Apr 2006 15:10:35 -0600 > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3227958636_24214829 Content-type: text/plain; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Vic, Marius, A further thought. chol is a .oct file. Are other .oct files (trisolve.oct, etc.) working? It may be a dynamic load library problem. The HPC version of octave was compiled on OS X 10.3.9, and, as I recall, Vic is running 10.4.x= . Joe on 4/15/06 2:53 PM, Joe Koski at jkoski11 at comcast dot net wrote: > Vic, Marius, >=20 > It must be the HPC version. On my home built with g95 version: >=20 > octave:1> C =3D [36 24; 24 25]; > octave:2> chol(C); > octave:3> chol(C) > ans =3D >=20 > 6 4 > 0 3 > Upper Triangular >=20 > octave:4> version > ans =3D 2.1.73 > =20 >=20 > Joe >=20 >=20 > on 4/15/06 2:29 PM, Marius Schamschula at marius173 at mchsi dot com wrote: >=20 >> Vic, >>=20 >> Is this the port from hpc.sf.net, or did you compile from source? >>=20 >> I have yet to get a working build of octave 2.1.73 on the Mac. >>=20 >> On Apr 15, 2006, at 3:16 PM, Vic Norton wrote: >>=20 >>> I had thought Octave, version 2.1.73, was working fine on my iMac G5, >>> but now I'm not so sure. Here's my problem. >>>=20 >>> I start with the matrix >>> =A0=A0 octave> C =3D [36 24; 24 25]; >>> and do >>> =A0=A0 octave> chol(C); >>> After waiting for a while I get >>> =A0=A0 panic: Bus error -- stopping myself... >>> =A0=A0 attempting to save variables to `octave-core'... >>> =A0=A0 save to `octave-core' complete >>> =A0=A0 Bus error >>> =A0=A0 vic$ >>>=20 >>> To tell you the truth I'm not sure what the Cholesky factor of C is >>> supposed to be. I do know that C =3D R' * R where >>> =A0=A0 R =3D [0 3; 6 4]. >>> I have no problem computing another R that does this job: >>> =A0=A0 octave> C =3D [36 24; 24 25]; >>> =A0=A0 octave> [U, S, V] =3D svd(C); >>> =A0=A0 octave> R =3D sqrt(S) * V'; >>> Now >>> =A0=A0 R =3D [ >>> =A0 =A0 =A0 =A0 =A0 -5.8067=A0 -4.6265 >>> =A0 =A0 =A0 =A0 =A0 -1.5108 =A0 1.8962 >>> =A0=A0 =A0 =A0 ] >>> and C =3D R' * R for this R as well. But R =3D chol(C) simply doesn't work >>> for me. >>>=20 >>> Is anybody else having any problems with "chol" or is it just my screwe= d >>> up system? >>>=20 >>> Regards, >>>=20 >>> Vic >>=20 >>=20 >> =20 >>=20 >> Marius >>=20 >> -- >>=20 >> Marius Schamschula =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Webmaster >>=20 >>=20 >>=20 >> =A0 =A0 =A0 =A0 The Huntsville Macintosh Users Group >>=20 >> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 www.hmug.org >>=20 >>=20 >>=20 >> webmaster at hmug dot org=A0 =A0 marius at schamschula dot com >>=20 >>=20 >> =20 >>=20 >>=20 >=20 >=20 --B_3227958636_24214829 Content-type: text/html; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Re: chol? Vic, = Marius,

A further thought. chol is a .oct file. Are other .oct files (trisolve.oct,= etc.) working? It may be a dynamic load library problem. The HPC version of= octave was compiled on OS X 10.3.9, and, as I recall, Vic is running 10.4.x= .

Joe


on 4/15/06 2:53 PM, Joe Koski at jkoski11 at comcast dot net wrote:

Vic, Marius,

It must be the HPC version. On my home built with g95 version:

 octave:1> C =3D [36 24; 24 25];
 octave:2> chol(C);
 octave:3> chol(C)
 ans =3D

   6  4
   0  3
 Upper Triangular

 octave:4> version
 ans =3D 2.1.73
 

Joe


on 4/15/06 2:29 PM, Marius Schamschula at marius173 at mchsi dot com wrote:

Vic,

Is this the port from hpc.sf.net, or did you compile from source?

I have yet to get a working build of octave 2.1.73 on the Mac.

On Apr 15, 2006, at 3:16 PM, Vic Norton wrote:

I had thought Octave, version 2.1.73, was working fine = on my iMac G5,
but now I'm not so sure. Here's my problem.

I start with the matrix
=A0=A0 octave> C =3D [36 24; 24 25];
and do
=A0=A0 octave> chol(C);
After waiting for a while I get
=A0=A0 panic: Bus error -- stopping myself...
=A0=A0 attempting to save variables to `octave-core'...
=A0=A0 save to `octave-core' complete
=A0=A0 Bus error
=A0=A0 vic$

To tell you the truth I'm not sure what the Cholesky factor of C is
supposed to be. I do know that C =3D R' * R where
=A0=A0 R =3D [0 3; 6 4].
I have no problem computing another R that does this job:
=A0=A0 octave> C =3D [36 24; 24 25];
=A0=A0 octave> [U, S, V] =3D svd(C);
=A0=A0 octave> R =3D sqrt(S) * V';
Now
=A0=A0 R =3D [
=A0 =A0 =A0 =A0 =A0 -5.8067=A0 -4.6265
=A0 =A0 =A0 =A0 =A0 -1.5108 =A0 1.8962
=A0=A0 =A0 =A0 ]
and C =3D R' * R for this R as well. But R =3D chol(C) simply doesn't work
for me.

Is anybody else having any problems with "chol" or is it just my = screwed
up system?

Regards,

Vic


 

Marius

--

Marius Schamschula =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Webmaster



=A0 =A0 =A0 =A0 The Huntsville Macintosh Users Group

=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 www.hmug.org <http://w= ww.hmug.org>



webmaster at hmug dot org=A0 =A0 marius at schamschula dot com


 





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