Editing User:Andy1978


== ToDo ==

=== Core ===
* <strike>fix imread bug with opaque images, see https://savannah.gnu.org/bugs/?func=detailitem&item_id=36820</strike> Thanks Carne
* <strike>FFTW multithreaded</strike> hg.savannah.gnu.org/hgweb/octave/rev/bde7731b2b83
* <strike>remove removed but still referenced function in "seealso" blocks</strike>

* Add swisdom (single prec.) to /libinterp/dldfcn/fftw.cc documentation
* linguist-qt4: octave-src/libgui$ "lupdate -recursive -no-obsolete -locations relative src qterminal graphics -ts languages/*ts"

=== GUI ===
<strike>When opening and closing the GUI HDF5: infinite loop closing library</strike> [http://hg.savannah.gnu.org/hgweb/octave/rev/9c03b071fd7b]

No icons in qt4 GUI?
  gconftool-2 --type boolean --set /desktop/gnome/interface/buttons_have_icons true
  gconftool-2 --type boolean --set /desktop/gnome/interface/menus_have_icons true

=== Forge ===

==== signal or fltk plotting? ====
  pkg load signal
  t=0:1/4e4:12;
  y=chirp(t,100,5,18000);
  graphics_toolkit fltk
  specgram(y)

-> r300: Implementation error: Render targets are too big in r300_set_framebuffer_state, refusing to bind framebuffer state!

==== video ====
<strike>fix build, see http://octave.1599824.n4.nabble.com/quot-package-video-is-empty-quot-td4656346.html</strike>

==== signal ====
* findpeaks.m, print error if data is not a column vector (error: vertical dimensions mismatch (1x10000 vs 1x1)

==== FAQ for windows user ====

octave-forge packages on windows

You should follow the README for the binary octave bundle, for example
http://wiki.octave.org/Octave_for_Windows#Octave-3.6.4-mingw_.2B_octaveforge_pkgs

The additional forge-pkgs (ex. Octave3.6.4_gcc4.6.2_pkgs_20130331.7z) contains the already compiled
packages for the specific (Octave-3.6.4) version.

Normally windows users can't just install octave forge packages with
  pkg install package
or
  pkg install -forge package
because their system lacks a build system with autotools, make, c++ compiler etc.

==== image ====

* implement [http://en.wikipedia.org/wiki/SURF SURF], integralImage is cumsum(cumsum(a,1),2)
* implement impixelinfo http://stackoverflow.com/questions/23706937/displaying-pixel-values-of-an-image-in-octave
* implement getpixelposition, axes2pix, pix2map, map2pix

===== corner/cornermetric, harris =====

First post on mailing list in 12.01.2013 http://octave.1599824.n4.nabble.com/corner-cornermetric-equivalent-in-octave-td4648802.html

== Snippets ==
=== chain matrix multiplication ===
 a=[1 2; 3 4];
 b=[4 2; 8 1];
 c=[2 3; 1 -1];
 m=cat(3,a,b,c);
 s=cell(3,1);
 s{1}=a;s{2}=b; s{3}=c;
 a*b*c
 s{1}*s{2}*s{3}
 mtimes(num2cell(m,[1,2]){:})
 mtimes(s{:})

=== commands from which I regularly doesn't find the name ===
* octave_config_info ()
* merge (C's (a)? b: c); syntax

=== libgraphicsmagick++3 quantum-depth ===

in debian wheezy

 sudo apt-get build-dep libgraphicsmagick++3
 apt-get source libgraphicsmagick++3

edit debian/rules
 --with-quantum-depth=16 \
works without problems
 --with-quantum-depth=32 \
shows one error:
 UYVY format ...
 mean-error=0.0209018218321559, maximum-error=0.816509137487552
 not ok 77
 Failed 1/77 subtests 

 debuild -i -us -uc -b
 dpkg -i ....

== Tracking octave bugs with hg bisect==
I had a [http://savannah.gnu.org/bugs/?39652 strange problem] when loading gzip compressed ascii files in octave. It failed dependent on the integer values. After some stripping I made a minimalistic test script (min_testcase_fails.m) which always fails in a current dev (88616c872933):
 fn="file2.txt"
 fid = fopen (fn,"w");
 fprintf(fid, "%i %i %i %i\n",639, 25, 160, 978160);
 fprintf(fid, "%i %i %i %i\n",687, 25, 171, 978160);
 fprintf(fid, "%i %i %i %i\n",663, 31, 173, 978161);
 fprintf(fid, "%i %i %i %i\n",663, 15, 154, 978161);
 fprintf(fid, "%i %i %i %i\n",655, 21, 151, 978161);
 fclose(fid);
 ## gzip it!
 fn_gz=strcat(fn, ".gz");
 cmd=cstrcat("gzip ",fn," -c > ",fn_gz)
 system(cmd);
 c=load("file2.txt.gz")  #this fails in newer versions

When run:
 $ octave -q min_testcase_fails.m 
 fn = file2.txt
 cmd = gzip file2.txt -c > file2.txt.gz
 error: value on right hand side of assignment is undefined
 error: called from:
 error:   /home/andy/src/octave-bugs/min_testcase_fails.m at line 17, column 2

If line 4 with "663, 15, 154, 978161" is changed to ""663, 16, 154, 978161", load works as expected. '''Strange, isn't it?'''
I also had an old build (dev ab1c6e6d1be6 from Sun Oct 28 21:48:02 2012) and "load" worked in this version.

=== Running bisect ===
I decided to make a fresh clone in a separate directory:
 cd ~/src
 hg clone http://www.octave.org/hg/octave octave-src
 cd octave-src
 hg bisect -b 88616c872933
 hg bisect -g ab1c6e6d1be6
After this hg bisect uses a binary search strategy to test revisions:
 Teste Änderungssatz 16428:f016a5342e19 (1380 Änderungssätze verbleiben, ~10 Tests)
So after checkout I had to compile the source tree (used ccache in the hope of faster checkout-compile cycles).
 ./bootstrap
 cd .. && mkdir octave-build && cd octave-build
 export CXX="ccache g++"
 export CC="ccache gcc"
 ../octave-src/configure
 make -j 7
After compilation I tried my test min_testcase_fails.m:
<pre>~/src/octave-build$ ./run-octave -q ../min_testcase_fails.m
fn = file2.txt
cmd = gzip file2.txt -c > file2.txt.gz
c =

      639       25      160   978160
      687       25      171   978160
      663       31      173   978161
      663       15      154   978161
      655       21      151   978161
</pre>
So this is apparently a good one. Tell it hg bisect!

 cd ../octave-src && hg bisect -g

After this you try make again, bootstrap && configure if make fails, rerun the testscript, tell hg bisect if it's good or bad and repeat this until the revision which introduced the problem is found.
Or you can use "hg bisect --command", see next point.

=== hg bisect --command ===
I used [http://jordi.platinum.linux.pl/tmp/bisect-32818.sh Jordis bisect script for bug 32818] and modified it to my needs:
 ~/src$ cat bisect-loadsave.sh 
 #!/bin/bash
 SRCDIR=~/src/octave-src
 BUILDDIR=~/src/octave-build
 cd $SRCDIR
 ## Try a simple build first
 if  ! make -j 7
 then
    cd $SRCDIR
    ./bootstrap || exit 127
    #rm -rf $BUILDDIR
    #mkdir $BUILDDIR
    cd $BUILDDIR
    $SRCDIR/configure || exit 127
    make -j 7|| exit 127
 fi
 $BUILDDIR/run-octave -q ~/src/min_testcase_fails.m || exit 1
 exit 0

After making it executable, let hg bisect use it
 ~/src/octave-src$ hg bisect -c ../bisect-loadsave.sh

Now sit back and relax, this could last some hours... Finally:
<pre>Änderungssatz 16554:03a28487fa9d: good
Die erste fehlerhafte Revision ist:
Änderung:        16555:04fb96f4bea1
Nutzer:          John W. Eaton <jwe@octave.org>
Datum:           Tue Apr 23 12:57:16 2013 -0400
Zusammenfassung: allow double-click in file browser to load data files</pre>


=== bisect bug 42612 ===

For bug #42612 I created a minimal script which fails: clf_fails_42612.m
 subplot (2,1,1);
 plot (1:5);
 legend ('hello', 'location', 'northwestoutside');
 clf

And the script which runs it, bisect_clf.sh:
 #!/bin/bash
 SRCDIR=~/src/octave-untouched-src
 BUILDDIR=~/src/bisect_build
 cd $BUILDDIR
 ## Try a simple build first
 if  ! make -j 6
 then
   # make failed, run bootstrap and configure
   cd $SRCDIR
   ./bootstrap || exit 127
   cd $BUILDDIR
   $SRCDIR/configure FFLAGS=-g CFLAGS=-g CXXFLAGS=-g --enable-bounds-check --disable-java --disable-gui --disable-docs|| exit 127
   make -j 7|| exit 127
 fi
 cd $SRCDIR
 $BUILDDIR/run-octave -q clf_fails_42612.m
 ret=$?
 echo $(hg id) $ret >> clf_fails_42612.log
 exit $ret

=== show bisect history ===

 hg log -r "bisect(good) or bisect(bad)" --template "{rev}:{node|short} {bisect}\n"

== Links ==

* [http://hg.code.sf.net/p/octave/image hgweb on sourceforge]
* [http://mywiki.wooledge.org/BashFAQ/073 bash parameter expansion]