[vtkusers] Re: vtkusers digest, Vol 1 #969 - 12 msgs
L.O.Q. Hector Salas
hsalas at grupomar.com
Tue Apr 23 16:52:05 EDT 2002
Amor estás allí?
----- Original Message -----
From: <vtkusers-request at public.kitware.com>
To: <vtkusers at public.kitware.com>
Sent: Tuesday, April 23, 2002 2:44 PM
Subject: vtkusers digest, Vol 1 #969 - 12 msgs
> Send vtkusers mailing list submissions to
> vtkusers at public.kitware.com
>
> To subscribe or unsubscribe via the World Wide Web, visit
> http://public.kitware.com/mailman/listinfo/vtkusers
> or, via email, send a message with subject or body 'help' to
> vtkusers-request at public.kitware.com
>
> You can reach the person managing the list at
> vtkusers-admin at public.kitware.com
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of vtkusers digest..."
>
>
> Today's Topics:
>
> 1. Importing 3DS and VRML files. (Allan Reinhold Jensen)
> 2. Problems with VtkColorBar (Giancarlo Amati)
> 3. Problems with VTK and PyQt 3.1 (Prof. Andreas Gerber)
> 4. Re: Importing 3DS and VRML files. (Robert Belleman)
> 5. Re: Importing 3DS and VRML files. (Allan Reinhold Jensen)
> 6. Re: Importing 3DS and VRML files. (Robert Belleman)
> 7. Re: Importing 3DS and VRML files. (Berk Geveci)
> 8. Re: how to get outline from CT images (Goodwin Lawlor)
> 9. Building VTK on MAC OSX (Daniel =?iso-8859-15?q?S=E1ez=20Domingo?=)
> 10. vtkImagePlaneWidget.cxx (Dean Inglis)
> 11. Re: Building VTK on MAC OSX (Sander Niemeijer)
> 12. ClassifyFirst vs. InterpolateFirst (Dave Reed)
>
> --__--__--
>
> Message: 1
> To: vtkusers at public.kitware.com
> From: "Allan Reinhold Jensen" <arj at tm-net.dk>
> Date: Tue, 23 Apr 2002 15:09:16 +0200
> Subject: [vtkusers] Importing 3DS and VRML files.
>
> Hi.
>
> Is there any way to get the number og geometric objects from the
> vtkRenderer class when importing from 3DS or VRML files? I am in the
> process of making a small command line tool using C++ and VTK which can=
>
> read a 3DS or VRML file and save it into a VTK PolyData file. The tool
> works fine, but if the file contains more than one object, I would like=
> to
> print out a warning to the user. I can only seem to find the total numb=
> er
> of objects, including lights and cameras, and furthermore, all objects
> imported from the 3DS or VRML file are of type vtkOpenGLActor, which ma=
> kes
> it hard to determine type (light, camera etc).
>
> Any suggestions? Feel free to mail any answer.
>
> Best regards,
> Allan Reinhold
>
> * Allan Reinhold - mailto:arj at tm-net.dk
> * Theilgaard Mortensen A/S
> * Niels Hemmingsens Gade 9, 4.
> * 1153 K=F8benhavn K
> * Pho/Mob: +45 33448555 / 26818969
> * http://www.tm-net.dk
>
> "We collaboratively negotiate progressive deliverables such that we may=
>
> continue to proactively revolutionize scalable content" - Dilbert, 200=
> 1=
>
>
>
> --__--__--
>
> Message: 2
> Date: Tue, 23 Apr 2002 16:03:55 +0200 (CEST)
> From: Giancarlo Amati <amati at ira.cnr.it>
> To: <vtkusers at public.kitware.com>
> Subject: [vtkusers] Problems with VtkColorBar
>
> Hi everybody,
>
> I have this question, I'm mapping X, and Y and Z coordinate in a color
> bar. I used vtkScalarBarActor and I have created one for X , one for Y and
> one for Z.
> I add my Bar to the renderer with AddActor2D and I remove it wit
> RemoveActor. The problem is that I create the three bars with the same
> font caracther and with the same width size, but when I switch from a
> color bar to another my bars change width and caracther size.
>
> Could be a bug of Vtk or am I forgotting something?
> When I switch to another bar I siply remove the current bar from the
> renderer and I will add the new that I want to display.
>
> Can anybody help me?
>
> Thank you very much and sorry for my english.
>
> Giancarlo
>
> --
> ----------------------------------------
> dott. Giancarlo Amati |
> (amati at ira.cnr.it) |
> |
> National Research Council |
> RadioAstronomical Institute |
> office phone n. +39 051 6399405 |
> via Gobetti 101 - Bologna (Italy) |
> ----------------------------------------
>
>
> --__--__--
>
> Message: 3
> From: "Prof. Andreas Gerber" <gerber at fh-biberach.de>
> Reply-To: gerber at fh-biberach.de
> Organization: Fachhochschule Biberach
> To: vtkusers at public.kitware.com
> Date: Tue, 23 Apr 2002 16:38:49 +0200
> Subject: [vtkusers] Problems with VTK and PyQt 3.1
>
> Hi,
> I found a strange behaviour while trying to upgrade from PyQt 3.0 (QT 2.3)
to
> PyQt 3.1 (QT 3.0.3) under Suse 8.0 and vtk 4.0, python 2.2. The example
code
> in QVTKRenderWidget.py works well with both versions of PyQt.
> But if I add a non-empty ToolBar to my application the main window doesn't
> appear and CPU load reaches 100 %.
>
> Andreas
>
> --__--__--
>
> Message: 4
> Date: Tue, 23 Apr 2002 16:39:10 +0200
> From: Robert Belleman <robbel at science.uva.nl>
> To: Allan Reinhold Jensen <arj at tm-net.dk>
> Cc: vtkusers at public.kitware.com
> Subject: Re: [vtkusers] Importing 3DS and VRML files.
>
> Allan,
>
> On Tue, Apr 23, 2002 at 03:09:16PM +0200, Allan Reinhold Jensen wrote:
> > Is there any way to get the number og geometric objects from the
> > vtkRenderer class when importing from 3DS or VRML files?
>
> I would expect the following to give you the number of objects (i.e.
> actors) only:
>
> vtkVRMLImporter *importer = vtkVRMLImporter::New();
> // or vtk3DSImporter *importer = vtk3DSImporter::New();
> importer->SetRenderWindow(your_render_window);
> importer->SetFileName(filename);
> importer->Read();
>
> int nactors = importer->GetRenderer()->GetActors()->GetNumberOfItems();
>
> (this is from memory; so there might be a typo in there)
> Did you try that?
>
> Of course, this all relies on the fact that the different objects
> were in fact saved as different objects by the application that
> generated the VRML/3DS file in the first place.
>
> -- Rob
>
> --
> [] Robert Belleman X Section Computational Science []
> [] robbel at science.uva.nl |X| University of Amsterdam, the Netherlands []
> [] tel: (+31) 20 525 7510 X http://www.science.uva.nl/~robbel/ []
>
> --__--__--
>
> Message: 5
> Subject: Re: [vtkusers] Importing 3DS and VRML files.
> To: Robert Belleman <robbel at science.uva.nl>
> Cc: vtkusers at public.kitware.com
> From: "Allan Reinhold Jensen" <arj at tm-net.dk>
> Date: Tue, 23 Apr 2002 17:04:14 +0200
>
>
> Hi Rob.
>
> I did try the GetNumberOfItems() function, however this only tells me h=
> ow
> many items the list contains, and not their type. The item list contain=
> s
> geometrical objects as well as lights, cameras etc. If I enable the
> debugger with importer->DebugOn(), I can see it loads a set of polygons=
> , a
> camera, and some lightsources. This is all printed out in the debug win=
> dow.
>
> Best regards,
>
> Allan Reinhold
>
> * Allan Reinhold - mailto:arj at tm-net.dk
> * Theilgaard Mortensen A/S
> * Niels Hemmingsens Gade 9, 4.
> * 1153 K=F8benhavn K
> * Pho/Mob: +45 33448555 / 26818969
> * http://www.tm-net.dk
>
> "We collaboratively negotiate progressive deliverables such that we may=
>
> continue to proactively revolutionize scalable content" - Dilbert, 200=
> 1
>
>
> =
> =
>
> Robert =
> =
>
> Belleman To: Allan Reinhold Jensen =
> <arj at tm-net.dk> =
>
> <robbel at scienc cc: vtkusers at public.kitwar=
> e.com =
>
> e.uva.nl> Subject: Re: [vtkusers] Im=
> porting 3DS and VRML files. =
>
> =
> =
>
> 23-04-2002 =
> =
>
> 16:39 =
> =
>
> =
> =
>
> =
> =
>
>
>
>
>
> Allan,
>
> On Tue, Apr 23, 2002 at 03:09:16PM +0200, Allan Reinhold Jensen wrote:
> > Is there any way to get the number og geometric objects from the
> > vtkRenderer class when importing from 3DS or VRML files?
>
> I would expect the following to give you the number of objects (i.e.
> actors) only:
>
> vtkVRMLImporter *importer =3D vtkVRMLImporter::New();
> // or vtk3DSImporter *importer =3D vtk3DSImporter::New();
> importer->SetRenderWindow(your_render_window);
> importer->SetFileName(filename);
> importer->Read();
>
> int nactors =3D importer->GetRenderer()->GetActors()->GetNumberOfItem=
> s();
>
> (this is from memory; so there might be a typo in there)
> Did you try that?
>
> Of course, this all relies on the fact that the different objects
> were in fact saved as different objects by the application that
> generated the VRML/3DS file in the first place.
>
> -- Rob
>
> --
> [] Robert Belleman X Section Computational Science =
> []
> [] robbel at science.uva.nl |X| University of Amsterdam, the Netherlands =
> []
> [] tel: (+31) 20 525 7510 X http://www.science.uva.nl/~robbel/ =
> []
>
>
> =
>
>
>
> --__--__--
>
> Message: 6
> Date: Tue, 23 Apr 2002 17:13:40 +0200
> From: Robert Belleman <robbel at science.uva.nl>
> To: Allan Reinhold Jensen <arj at tm-net.dk>
> Cc: vtkusers at public.kitware.com
> Subject: Re: [vtkusers] Importing 3DS and VRML files.
>
> On Tue, Apr 23, 2002 at 05:04:14PM +0200, Allan Reinhold Jensen wrote:
> > I did try the GetNumberOfItems() function, however this only tells me
how
> > many items the list contains, and not their type. The item list contains
> > geometrical objects as well as lights, cameras etc. If I enable the
> > debugger with importer->DebugOn(), I can see it loads a set of polygons,
a
> > camera, and some lightsources. This is all printed out in the debug
window.
>
> That's weird; the importer should read actors, lights and cameras
> separately. Well; I'm assuming that's what the protected methods
> ImportActors(), ImportCameras() and ImportLights() do in vtkImporter...
>
> And as these things are put into different collections, I would expect
> you get the number of items in that collection only (although I'm not
> sure what happens when there are multiple cameras, since there is no
> such thig as a vtkCameraCollection).
>
> What do you get when you call this?:
>
> int nlights = importer->GetRenderer()->GetLights()->GetNumberOfItems();
>
> -- Rob
>
> --
> [] Robert Belleman X Section Computational Science []
> [] robbel at science.uva.nl |X| University of Amsterdam, the Netherlands []
> [] tel: (+31) 20 525 7510 X http://www.science.uva.nl/~robbel/ []
>
> --__--__--
>
> Message: 7
> Subject: Re: [vtkusers] Importing 3DS and VRML files.
> From: Berk Geveci <berk.geveci at kitware.com>
> To: Allan Reinhold Jensen <arj at tm-net.dk>
> Cc: Robert Belleman <robbel at science.uva.nl>,
> vtkusers <vtkusers at public.kitware.com>
> Date: 23 Apr 2002 11:17:38 -0400
>
> You should be able to iterate over the items and inquire the=20
> class/superclass of each with the virtual IsA and IsTypeOf=20
> methods.
>
> -Berk
>
> On Tue, 2002-04-23 at 11:04, Allan Reinhold Jensen wrote:
> >=20
> > Hi Rob.
> >=20
> > I did try the GetNumberOfItems() function, however this only tells me
how
> > many items the list contains, and not their type. The item list contains
> > geometrical objects as well as lights, cameras etc. If I enable the
> > debugger with importer->DebugOn(), I can see it loads a set of polygons,
=
> a
> > camera, and some lightsources. This is all printed out in the debug
windo=
> w.
> >=20
> > Best regards,
> >=20
> > Allan Reinhold
> >=20
> > * Allan Reinhold - mailto:arj at tm-net.dk
> > * Theilgaard Mortensen A/S
> > * Niels Hemmingsens Gade 9, 4.
> > * 1153 K=F8benhavn K
> > * Pho/Mob: +45 33448555 / 26818969
> > * http://www.tm-net.dk
> >=20
> > "We collaboratively negotiate progressive deliverables such that we may
> > continue to proactively revolutionize scalable content" - Dilbert, 2001
> >=20
> >=20
> >
=
> =20
> > Robert
=
> =20
> > Belleman To: Allan Reinhold Jensen
<a=
> rj at tm-net.dk> =20
> > <robbel at scienc cc:
vtkusers at public.kitware.=
> com =20
> > e.uva.nl> Subject: Re: [vtkusers]
Impo=
> rting 3DS and VRML files. =20
> >
=
> =20
> > 23-04-2002
=
> =20
> > 16:39
=
> =20
> >
=
> =20
> >
=
> =20
> >=20
> >=20
> >=20
> >=20
> > Allan,
> >=20
> > On Tue, Apr 23, 2002 at 03:09:16PM +0200, Allan Reinhold Jensen wrote:
> > > Is there any way to get the number og geometric objects from the
> > > vtkRenderer class when importing from 3DS or VRML files?
> >=20
> > I would expect the following to give you the number of objects (i.e.
> > actors) only:
> >=20
> > vtkVRMLImporter *importer =3D vtkVRMLImporter::New();
> > // or vtk3DSImporter *importer =3D vtk3DSImporter::New();
> > importer->SetRenderWindow(your_render_window);
> > importer->SetFileName(filename);
> > importer->Read();
> >=20
> > int nactors =3D
importer->GetRenderer()->GetActors()->GetNumberOfItems(=
> );
> >=20
> > (this is from memory; so there might be a typo in there)
> > Did you try that?
> >=20
> > Of course, this all relies on the fact that the different objects
> > were in fact saved as different objects by the application that
> > generated the VRML/3DS file in the first place.
> >=20
> > -- Rob
> >=20
> > --
> > [] Robert Belleman X Section Computational Science
[]
> > [] robbel at science.uva.nl |X| University of Amsterdam, the Netherlands
[]
> > [] tel: (+31) 20 525 7510 X http://www.science.uva.nl/~robbel/
[]
> >=20
> >=20
> >=20
> >=20
> > _______________________________________________
> > This is the private VTK discussion list.=20
> > Please keep messages on-topic. Check the FAQ at:
<http://public.kitware.c=
> om/cgi-bin/vtkfaq>
> > Follow this link to subscribe/unsubscribe:
> > http://public.kitware.com/mailman/listinfo/vtkusers
>
>
>
> --__--__--
>
> Message: 8
> Date: Tue, 23 Apr 2002 16:04:26 +0100
> From: Goodwin Lawlor <goodwin.lawlor at ucd.ie>
> Subject: Re: [vtkusers] how to get outline from CT images
> To: ljhfdy4 <ljhfdy4 at sina.com>, vtkusers at public.kitware.com
>
> A quick outline:
> 1. Segment your ct image to a set of binary images (use vtkImageThreshold,
> vtkImageIslandRemove)
> 2. Use vtkMarchingSquares to extract 2d outlines (maybe pre-smooth with
> vtkImageGaussianSmooth)
> 3. Use vtkStripper to create polylines from the unordered lines from MS
>
> Cad package format is a tricky one... vtkSTLWriter doesn't spit out
> polylines. If you have AutoCad you can write a VB script to read the
> polyline coords and insert them into a scene as a closed spline.
>
> Check which VTK writer/exporter writes out polylines and then see if your
> CAD package can read the format
>
> HTH
>
> Goodwin
> ----- Original Message -----
> From: "ljhfdy4" <ljhfdy4 at sina.com>
> To: <vtkusers at public.kitware.com>
> Sent: Monday, April 22, 2002 11:51 PM
> Subject: [vtkusers] how to get outline from CT images
>
>
> > Hi, friends:
> >
> > I have a question about how to get the outline from CT images. What I
want
> to do is extracting the outline of a special tissue like bone or skin from
> one slice of CT (threshold may needed). In my idea the outline should be
> polyline, but I am not sure which functions can do this work exactly. Also
> how can i save the extracted polyline into a format the CAD packages can
> read? If impossible, image format is ok too.
> >
> > Thanks a lot for your help.
> >
> >
> > Ljh
> > ______________________________________
> >
> > ===================================================================
> > ÐÂÀËÃâ·Ñµç×ÓÓÊÏä (http://mail.sina.com.cn)
> > ÐÂÀË·ÖÀàÐÅÏ¢£º¶þÊÖÊг¡×ßÒ»×ߣ¬¸Ã³öÊÖʱ¾Í³öÊÖ£¡
> (http://classad.sina.com.cn/2shou/)
> > _______________________________________________
> > This is the private VTK discussion list.
> > Please keep messages on-topic. Check the FAQ at:
> <http://public.kitware.com/cgi-bin/vtkfaq>
> > Follow this link to subscribe/unsubscribe:
> > http://public.kitware.com/mailman/listinfo/vtkusers
>
>
> --__--__--
>
> Message: 9
> From: Daniel =?iso-8859-15?q?S=E1ez=20Domingo?= <dsaez at iti.upv.es>
> Organization: Instituto =?iso-8859-15?q?Tecnol=F3gico=20de?=
=?iso-8859-15?q?=20Inform=E1tica?=
> To: vtkusers at public.kitware.com
> Date: Tue, 23 Apr 2002 18:50:16 +0200
> Subject: [vtkusers] Building VTK on MAC OSX
>
> Hello,
>
> I am new in VTK's world. I have tried to build VTK on a MAC OS X but I
> have had a lot of problems.
> I have read the archives and I think my problem isn't solved there.
>
> I have done all the changes in the Rendering directory files (__APPLE__ by
> VTK_USE_QUARTZ) and in the CMakeList.txt and the options in CMakeCache.txt
are
> OPENGL_LIBRARY:FILEPATH=-framework AppKit -framework OpenGL
> VTK_USE_QUARTZ:BOOL=ON
> VTK_USE_RENDERING:BOOL=ON
> VTK_USE_X:BOOL=OFF
>
> but when I do make, it is produced the next error:
> /usr/local/src/VTK/Rendering/vtkOpenGLActor.cxx:50: GL/gl.h: No such file
or
> directory
>
>
> I have looked for the gl.h in my system and I've found the next file:
>
> /System/Library/Frameworks/OpenGL.frameworks/Versions/A/Headers/gl.h
>
> then, I have put this directory in the OPENGL_INCLUDE_PATH
>
> but the problem continues.
>
> I would like someone to help me, please.
>
> Thank you
>
> Daniel Sáez.
>
> --__--__--
>
> Message: 10
> From: "Dean Inglis" <dean.inglis at on.aibn.com>
> To: <vtkusers at public.kitware.com>
> Date: Tue, 23 Apr 2002 13:19:18 -0700
> Subject: [vtkusers] vtkImagePlaneWidget.cxx
>
> Hi all,
>
> officially added vtkImagePlaneWidget.cxx in vtk/Hybrid:
>
> a widget that allows interactive (orthogonal) slicing through vtkImageData
> sets...left, middle button do the pushing of the slice plane, right button
> does window/level.
>
> enjoy,
> Dean
>
>
> --__--__--
>
> Message: 11
> Date: Tue, 23 Apr 2002 19:53:51 +0200
> Subject: Re: [vtkusers] Building VTK on MAC OSX
> Cc: vtkusers at public.kitware.com
> To: =?ISO-8859-1?Q?Daniel_S=E1ez_Domingo?= <dsaez at iti.upv.es>
> From: Sander Niemeijer <niemeijer at science-and-technology.nl>
>
> Hi Daniel,
>
> If you want to compile for Quartz then you don't have to change the=20
> __APPLE__ definition checks to VTK_USE_QUARTZ. If you do apply the=20
> changes then one extra thing has to be added in order to get compiling=20=
>
> for Quartz to work again. In the Rendering/CMakeLists.txt you have to=20
> add the line
> ---
> ADD_DEFINITIONS(-DVTK_USE_QUARTZ)
> --
> in the 'IF (APPLE) IF (VTK_USE_QUARTZ)' section.
>
> Maybe a good time to summarize the possibillities you can use at the=20
> moment and how to get them to work:
>
> - If you have VTK 4.0 and want to compile with Quartz support then all=20=
>
> you have to do is set VTK_USE_QUARTZ to ON, VTK_USE_X to OFF and set
the=20=
>
> OPENGL_LIBRARY to -framework Appkit -framework OpenGL. (No need to=20
> change the __APPLE__ definition checks)
>
> - If you use the CVS version of VTK and want to compile with Quartz=20
> support then the OPENGL_LIBRARY setting will automatically be set=20
> properly (make sure that you also use the CVS version of CMake! And=20
> again no need to change the __APPLE__ defintion checks).
>
> - If you have VTK 4.0 and want to compile with X11 support then follow=20=
>
> the instructions you found in the mailinglist archive and add the=20
> ADD_DEFINITIONS setting so you will also be able to compile with
Quartz=20=
>
> support from the same sourcetree.
>
> - If you use the CVS version of VTK and want to compile with X11
support=20=
>
> then please have some patience (or drop me an e-mail if you really
can't=20=
>
> wait ;-). As I understood from Yves, he will soon be adding the patch
to=20=
>
> CVS that will support both X11 and Quartz builds of VTK on Mac OS X.
>
> Regards,
> Sander
>
> On dinsdag, april 23, 2002, at 06:50 , Daniel S=E1ez Domingo wrote:
>
> > Hello,
> >
> > I am new in VTK's world. I have tried to build VTK on a MAC OS X=20
> > but I
> > have had a lot of problems.
> > I have read the archives and I think my problem isn't solved there.
> >
> > I have done all the changes in the Rendering directory files =
> (__APPLE__=20
> > by
> > VTK_USE_QUARTZ) and in the CMakeList.txt and the options in=20
> > CMakeCache.txt are
> > OPENGL_LIBRARY:FILEPATH=3D-framework AppKit -framework OpenGL
> > VTK_USE_QUARTZ:BOOL=3DON
> > VTK_USE_RENDERING:BOOL=3DON
> > VTK_USE_X:BOOL=3DOFF
> >
> > but when I do make, it is produced the next error:
> > /usr/local/src/VTK/Rendering/vtkOpenGLActor.cxx:50: GL/gl.h: No such=20=
>
> > file or
> > directory
> >
> >
> > I have looked for the gl.h in my system and I've found the next file:
> >
> > /System/Library/Frameworks/OpenGL.frameworks/Versions/A/Headers/gl.h
> >
> > then, I have put this directory in the OPENGL_INCLUDE_PATH
> >
> > but the problem continues.
> >
> > I would like someone to help me, please.
> >
> > Thank you
> >
> > Daniel S=E1ez.
> > _______________________________________________
> > This is the private VTK discussion list.
> > Please keep messages on-topic. Check the FAQ at:=20
> > <http://public.kitware.com/cgi-bin/vtkfaq>
> > Follow this link to subscribe/unsubscribe:
> > http://public.kitware.com/mailman/listinfo/vtkusers
> >
>
>
> --__--__--
>
> Message: 12
> Date: Tue, 23 Apr 2002 15:42:46 -0400 (EDT)
> From: Dave Reed <dreed at capital.edu>
> To: vtkusers at public.kitware.com
> Subject: [vtkusers] ClassifyFirst vs. InterpolateFirst
>
>
> Can anyone explain the difference between these two compositing
> functions for me?
>
> vtkVolumeRayCastCompositeFunction::SetCompositeMethodToInterpolateFirst
> vtkVolumeRayCastCompositeFunction::SetCompositeMethodToClassifyFirst
>
> And in general, is there somewhere that explains concepts like this? I
> have the Prentice Hall VTK book and have looked at the online HTML
> documentation. I took a quick glance at the
> vtkVolumeRayCastCompositeFunction.cxx file but I couldn't decipher the
> differences between:
>
> CastRay_TrilinVertices_Unshaded
> CastRay_TrilinSample_UnShaded
>
> From the looks of the table of contents it does not appear that the
> manual Kitware sells will help with this type of information or am I
> wrong?
>
> Thanks,
> Dave
>
>
> --__--__--
>
> _______________________________________________
> vtkusers mailing list
> vtkusers at public.kitware.com
> http://public.kitware.com/mailman/listinfo/vtkusers
>
>
> End of vtkusers Digest
More information about the vtkusers
mailing list