[Pkg-octave-devel] Bug#295395: [dnj@x.dtu.dk: octave-forge: Replacing a submatrix of a sparse matrix results in a full matrix]

[Rafael Laboissiere]

package octave-forge
tags 295395 upstream
forwarded 295395 octave-dev@lists.sourceforge.net
thanks

----- Forwarded message from Dennis Jørgensen <dnj@x.dtu.dk> -----

From: Dennis Jørgensen <dnj@x.dtu.dk>
Subject: octave-forge: Replacing a submatrix of a sparse matrix results in a full
 matrix
Date: Tue, 15 Feb 2005 16:28:50 +0100
To: Debian Bug Tracking System <submit@bugs.debian.org>

Package: octave-forge
Version: 2004.11.16-3
Severity: normal


With the following commands, I would have expected matrix A to
stay sparse:

octave:1> A = sparse(4,4);
octave:2> A([1 2 4],[1 2 4]) = sprand(3,3,0.2);
octave:3> issparse(A)
ans = 0


Same commands in Matlab:


>> A = sparse(4,4);     
>> A([1 2 4],[1 2 4]) = sprand(3,3,0.2);
>> issparse(A)

ans =

     1


Replacing sprand() with something returning a full matrix yields
the same results: sparse 'A' in Matlab, full in Octave.



Regards,


  Dennis J??rgensen


-- System Information:
Debian Release: 3.1
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: i386 (i686)
Kernel: Linux 2.6.8-2-k7
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)

Versions of packages octave-forge depends on:
ii  atlas3-base [liblapack.s 3.6.0-19        Automatically Tuned Linear Algebra
ii  atlas3-sse [liblapack.so 3.6.0-19        Automatically Tuned Linear Algebra
ii  fftw3                    3.0.1-11        Library for computing Fast Fourier
ii  libc6                    2.3.2.ds1-20    GNU C Library: Shared libraries an
ii  libcln3                  1.1.9-1         Class Library for Numbers (C++)
ii  libg2c0                  1:3.3.5-8       Runtime library for GNU Fortran 77
ii  libgcc1                  1:3.4.3-9       GCC support library
ii  libginac1.3              1.3.0-2         The GiNaC framework (runtime libra
ii  libgmp3                  4.1.4-5         Multiprecision arithmetic library
ii  libgsl0                  1.6-1           The GNU Scientific Library (GSL) -
ii  libhdf5-serial-1.6.2-0 [ 1.6.2-3         Hierarchical Data Format 5 (HDF5) 
ii  libice6                  4.3.0.dfsg.1-10 Inter-Client Exchange library
ii  libjpeg62                6b-9            The Independent JPEG Group's JPEG 
ii  libncurses5              5.4-4           Shared libraries for terminal hand
ii  libpng12-0               1.2.8rel-1      PNG library - runtime
ii  libqhull5                2003.1-1        Calculate convex hulls and related
ii  libreadline4             4.3-15          GNU readline and history libraries
ii  libsm6                   4.3.0.dfsg.1-10 X Window System Session Management
ii  libstdc++5               1:3.3.5-8       The GNU Standard C++ Library v3
ii  libx11-6                 4.3.0.dfsg.1-10 X Window System protocol client li
ii  octave2.1                2.1.64-3        GNU Octave language for numerical 
ii  xlibs                    4.3.0.dfsg.1-11 X Keyboard Extension (XKB) configu
ii  zlib1g                   1:1.2.2-4       compression library - runtime

-- no debconf information



----- End forwarded message -----

-- 
Rafael