- Chimera-users - RBVI Mailing Lists

Chimera on 64-bit Windows
by Tom Goddard 21 Feb '07

21 Feb '07

Hi Christopher, I believe the 32-bit Windows Chimera distribution will run on 64-bit versions of Windows, such as Windows XP Pro x64 Edition. But I do not have a machine to try it on. It will certainly run on 32-bit Windows running on a 64-bit processor -- I've tried that with an AMD64 processor. Tom Christopher Akey wrote: > Steve and Tom- > > Will EMAN and Chimera run ok on a 64 bit machine running windows XP, > initially we plan to use it this way, then change over to Linux when > we have time. Or do we just install Linux right away? > > cheers C Akey

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Memory requirements for Chimera
by Tom Goddard 21 Feb '07

21 Feb '07

Hi Christopher, I think it starts making sense to use a 64-bit machine if you are loading data that requires >= 1 Gbyte. In general, 32-bit linux binaries will run on a 64-bit machine. Currently we only provide a 32-bit linux Chimera distribution though we plan on adding 64-bit Linux as a standard Chimera platform in the next 6 months. The 32-bit Chimera runs fine on 64-bit linux. The advantage of a 64-bit version is that it uses memory pointers that are 64 bits so they can address more than 4 Gbytes. On a 32-bit system the operating system and the many libraries that Chimera uses (~50) may occupy a significant portion of the 4 Gbyte address space. Even if you have less than 4 Gbytes of physical memory the operating system can and does use the full 32-bit 4 Gbyte address space and swap data to disk when there is not enough physical memory. But if a program asks for a 512 Mbyte block of memory and there is no available segment of that size in the address space then it will fail. Graphics drivers use the computer's main memory for data that will not fit on the card. Either 256 or 512 Mbytes on the graphics card should give good performance even for large systems. Unless you are using the volume "solid" rendering mode the rendering speed will slow to much less than 1 frame per second before you use up 256 Mbytes. For reference, the machines I currently use for developing Chimera and looking at large volume data sets are: 1) Mac dual G5 desktop with 1.5 Gbyte memory and 128 Mb ATI Radeon 9800 Pro graphics, and 2) MacBook Pro, Intel Core 2 duo, 2 Gbyte memory, 256 Mb ATI X1600 graphics. Thanks for the apoptosome papers -- interesting work. Tom Christopher Akey wrote: > Tom- > ok, I will keep notes on what is not working and send them to you, as > we go through making figures this week. > > Will chimera run fine on a 64 bit Linux box? The other option is 32 > bits, but if I buy a high end workstation it should probably be 64 bit > yes? > > Also, about making Chimera able to handle big sessions: is the rate > limiting factor the RAM or the memory on the Graphics Card. We have a > 512 Mb cache on our current graphics card and still have problems, so > I presume we are RAM limited. > > When buying a new machine, should I invest in a 512 Mb Nvidia card or > is 256 fine, as long as there is enough RAM? > > By the way, I am attaching two pdfs of papers published using Chimera > graphics. > > thanks. > > CWA > > > Tom Goddard wrote: >> Hi Christopher, >> >> I'm not sure what causes crashes in Chimera when you are working >> close to the available memory limit. If a memory allocation fails in >> C++ it should produce an error message in Chimera indicating that >> memory could not be allocated because we catch those exceptions. >> Memory allocations in C (not C++) libraries that Chimera uses are >> likely to cause a crash though. >> >> It would help us to know what Chimera is doing when the crashes >> occur. We may be able to put some safety checks in our C++ where C >> library allocations are known to fail. Do I understand correctly >> that crashes happen while you are saving an image (individual tiles >> being displayed on screen)? Chimera by default makes an image 3 >> times larger then requested to make a smoother image. That can take >> a good bit of memory. Are there other actions that cause crashes? >> >> Tom > >

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An NMR Average Structure
by S W Simon Sham 21 Feb '07

21 Feb '07

Hi, I need to calculate an average structure from an emsembled structures in Chimera. Can we do it it Chimera? If yes, how? Thanks for any helps. Simon ------------------------------------------------------------------------ ----- Simon Sham, Ph.D. NMR Core Facility Comprehensive Cancer Center Univerisity of Alabama 933 South 19th Street CH19 B31 Birmingham, AL 35294 Office: (205) 934-5696 Fax : (205) 934-6475 Email : ssham44(a)uab.edu

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Create surface from markers
by Tom Goddard 20 Feb '07

20 Feb '07

Hi Jeff, Chimera cannot currently create a surface from markers placed with the volume path tracer tool. It would not be so hard to write some Python code to do this. Here is an example of Python code that creates a surface in Chimera: http://www.cgl.ucsf.edu/chimera/docs/ProgrammersGuide/Reference/surface.html Tom Jeff wrote: > hi Tom, > > is there a way to use a marker file just to render a surface (a > series/group of dots, just needing to be connected by a mesh)? for > instance, to represent a membrane. > > -Jeff

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Saving full map when zoning
by Tom Goddard 20 Feb '07

20 Feb '07

Hi Jean-Francois, You can save a map with the original map size while using volume zone by first pressing the the "Full" button in the Features / Subregion Selection panel of the volume dialog. Then use the File / Save Map As button. You can see what region will be saved by looking at the Features / Region Bounds panel (and you could type in new bounds there and press the Enter key instead of pressing the Full button). The volume zone capability (Features / Zone) normally uses a smaller box of data so that it is faster. Even when part of the surface is hidden by the zoning the whole surface within the box being used is computed and that is sometimes slow. Tom jean-francois menetret wrote: > > Hi Thomas, > > when using the zone option in Chimera, is it possible to have the size > of the saved mrc file (after zoning) be the same as the original file ? > > Best wishes > > Jean-Francois

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Re: [Chimera-users] demo made under Linux has bland atoms in Windows
by Elaine Meng 17 Feb '07

17 Feb '07

On Feb 16, 2007, at 7:55 PM, Kenward Vaughan wrote: > For me, the byatom coloration is there to begin with under Linux. The > ach shows up colored properly, as does the acetylcholinesterase. > Aha!! Problem solved!! I am 99.99% sure the difference is your preferences file. The demo itself does not say to color by element when the structure is opened. However, there is a New Molecules section of the Preferences in which you can say structures should be colored that way when they are opened. Most likely you have this set on your home Linux machine, but not in the Chimera preferences used on the Windows machines. Months ago we discussed the need for some way to indicate that preferences should be bypassed at startup and/or when opening structures. This option would be appropriate for use with demos or scripts to be shared among multiple users each having some arbitrary set of preferences settings. However, this option hasn't been added (nor are we sure how best to implement it)... thanks for the additional motivation to revisit that issue! The demos included with Chimera were made in a directory with a default preferences file. It is likely, however, that some users with nondefault New Molecules preferences have played them back and gotten a result different than intended. > > I've noticed rotation is slow under Windows, but v. nice with Linux > (about 7 seconds total). > It depends on the graphics capabilities of the system. It is slow on our home desktop computer (>5 years old - you can almost hear gears grinding) but fast on my laptop (1-2 years old). Happy demoing and please do contact us with any problems or suggestions, Elaine ----- Elaine C. Meng, Ph.D. meng(a)cgl.ucsf.edu UCSF Computer Graphics Lab and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html

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demo made under Linux has bland atoms in Windows
by Kenward Vaughan 16 Feb '07

16 Feb '07

...in a fashion, that is. A demo I plan on using at school (a Windows fortress, it is) displays all atoms as grey--no color (by element). The demo was created on a Linux machine (at my home). :( Any thoughts? Kenward ps. both versions of Chimera are the latest production version (2304). -- In a completely rational society, the best of us would aspire to be _teachers_ and the rest of us would have to settle for something less, because passing civilization along from one generation to the next ought to be the highest honor and the highest responsibility anyone could have. - Lee Iacocca

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saving map in different position
by Gabor Papai 16 Feb '07

16 Feb '07

Hi Tom, Is there a way to save a map with only transformation, or obtain the transformation matrix if I do a freehand transformation of an object? We would like to create a composite volume of several spheres. It would be the best to write a single map of several differently positioned spheres but I could also apply the transformation in IMAGIC if I would know the matrix. Thanks for helping! Regards, Gabor -- Gabor Papai IGBMC Department of Structural Biology and Genomics 1, rue Laurent Fries, BP 10142 67404 Illkirch, France phone +33-3-90244796 Fax +33-3-88653201 E-mail: papai(a)igbmc.u-strasbg.fr

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Re: [Chimera-users] making movies with MorphMap, exporting povray scenes, FitMapInMap
by Gatsogiannis, Christos 15 Feb '07

15 Feb '07

Hello Greg and Tom, povray: the assumed gamma-change was indeed the problem. Thank you very much! I´m waitin for the next snapshot release MorphMap: the updated version works correctly! Thanks! Do you maybe plan in the future on offering the possibility to save a density map also in different formats than mrc (situs, imagic .. etc) ? That would be very useful... Thanks again, Christos

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cavity cropped view
by Randy Heiland 15 Feb '07

15 Feb '07

What options exist in Chimera for letting me show only that portion of a protein that is "near" another smaller molecule? Specifically, I have a ligand in a cavity of a large protein and would like to eliminate the "clutter" of the protein away from the cavity of interest. Thanks, Randy

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making movies with MorphMap, exporting povray scenes, FitMapInMap
by Gatsogiannis, Christos 14 Feb '07

14 Feb '07

Dear Chimera users and developers, recently I used the new morph map tool and it worked very nice in my case. I encountered a problem while exporting the animation in any movie-format within Morphmap, I just get empty or very small files, which cannot be displayed in any media-player. I decided then to use the chimera-movie recorder utility to record the morphing animation and this worked fine (I´ve tested this with mpeg-2 format). At the moment I´m using the chimera-version 1.2309 in a SUSE LINUX 9.2 environment. Is this a version problem or a bug? Furthermore, I´ve exported some scenes in the povray format and I´ve noticed that the final images are of lower quality in comparison with images made some months ago with older chimera versions. I haven´t changed the povray-version, the rendering settings and the settings for the visualisation of my data in chimera (brightness etc...). The colors are too pale, I could send you some example-images if needed. I´ve tried also the Fit Map in Map tool recently and it worked perfectly (you sent this tool to a group-colleague some months ago). I´m wondering why you didn´t put this tool on the experimental site yet....and one more last question...after using Fit Map in Map, is there any possibility to save the "fitted" map with it´s new orientation? Thanks, Christos Christos Gatsogiannis Institute of Zoology Johannes Gutenberg University 55099 Mainz, Germany Tel: +49(0)6131-39-23091 email: gatsogia(a)uni-mainz.de

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Request for Chimera on CD
by Tom Goddard 13 Feb '07

13 Feb '07

Hi Zia, Our Chimera software can be downloaded from the web http://www.cgl.ucsf.edu/chimera/download.html We have never distributed it by CD. Perhaps we can do it. Our program needs about 512 Mbytes of computer memory. What operating system do you need it for? Windows? Linux? Mac OS X? Because almost all molecular structure and sequence data used in research is obtained from the web I suspect our software will be of limited use to you without internet access. Tom zia muhammad wrote: > Respected Dear Dr. > > I am teaching Bioinformatics at International Islamic University > Islamabad, Pakistan. I am teaching molecula Docking and Protein > Structure prediction, CHIMERA or HMMs methodology. I hvae done all > theoratical work but could not perform any practical due to lack of > softwares. I will thankful to you if you kindly provide me some basic > softwares in this respect. After basic knowledge and establishing > proper labs we will purchase relatd softwares but on initial basis we > need your help. I also could not download different softwares so can > you kindly send me on CD. > Your kind attention will be highly acknowledged. > > Please reply. > > Regards > > Zia > > > ******************************** > *Muhammad Zia* > *Room # 7, Hostel # 2* > *Quaid-i-Azam University,* > *Islamabad. Pakistan* > *45320* > *********************************ue

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display two volumes alternatively
by Montserrat Samso 13 Feb '07

13 Feb '07

Hi, I am trying to compare two cryoEM density maps of the same protein, the only difference between them is a conformational change. Is there a way to switch directly from one volume to the other without having to display both of them together in between? Thanks, Montserrat ------------------------------------------------------- Montserrat Samso, Ph.D. Assistant Professor Department of Anesthesia Research Brigham and Women's Hospital Harvard Medical School 75 Francis St. Boston, MA 02115 Tel: 617 7328107 Fax: 617 7326927 E-mail: msamso(a)zeus.bwh.harvard.edu -------------------------------------------------------- CONFIDENTIALITY NOTICE: This e-mail message, including any attachments, is for the sole use of the intended recipient(s). The information contained in this message may be private and confidential, and may also be subject to the work product doctrine. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message.

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programmatic representation
by Randy Heiland 12 Feb '07

12 Feb '07

I'd like to be able to set the representation (wire, stick, bs, cpk) of a model programmatically, in this case, from a plugin. I was trying the following, but the newly displayed model would always be displayed in wire: self.model = ReadSDF.readSDF(tmpfile.name) chimera.openModels.add(self.model) #Midas.represent('stick', self.model) Midas.represent('cpk', self.model) Suggestions? thanks, Randy

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Re: [Chimera-users] opacity for stick representation in chimera
by Elaine Meng 12 Feb '07

12 Feb '07

Hi Jerome, First make a transparent color and then use it on the atoms/bonds - there are a handful of routes. You can make the transparent color using the Color Editor (under Tools... Utilities; click the Opacity to get a slider for that, then adjust the red/green/blue/opacity sliders as desired). This color can be used on atoms/bonds, ribbons, whatever (depending on the current target setting under Actions.. Color) by choosing "Actions... Color... from editor" or it can be used in coloring commands using the color name "fromeditor" Color Editor description: http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/colortool.html Alternatively, you can make the transparent color with the command "colordef" and give it whatever name you want. The new color name can then be used in coloring commands. Color definitions are saved in sessions. Or, if you don't want to save sessions, just make a command file with all of your favorite color definitions and read it in whenever you want those colors defined. "colordef" man page: http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/colordef.html I hope this makes sense - feel free to write back if it doesn't! Best, E ----- Elaine C. Meng, Ph.D. meng(a)cgl.ucsf.edu UCSF Computer Graphics Lab and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html On Feb 11, 2007, at 5:14 PM, Jerome Nilmeier wrote: > Hi Elaine: > > I was wondering: can you adjust the opacity of the stick > representation in chimera? > > best, J

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xforms, cpk scale
by Randy Heiland 08 Feb '07

08 Feb '07

Is there a command to scale sphere of a CPK rep? Is there a command to save the current viewing transformation to a file and then read it back/apply it at a later time? Thanks, Randy

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Drawing Artifacts
by Albion Baucom 08 Feb '07

08 Feb '07

Using the latest stable current production release of Chimera, 1.2304, I have begun to experience some drawing problems that I never had in previous versions. Specifically I frequently get a thin wireframe rendering of my protein structure when I draw the structure as a ribbon with a volume open at the same time. This wire frame persists even when I turn the display of the molecule off in the model panel, and it also does not rotate or translate if the protein is selected as the only active object. In effect it leaves behind a ghost image. Curiously this representation alternates from a light gray/white color to black when I open dialog boxes. The artifact toggles on and off with the volume in some instances. My processing and graphics hardware have not changed recently, nor has operating system (Linux). I do not experience this behavior with my last version of Chimera, 1.2199; it never renders this artifact. I have a nVidia Geforce 6800GT graphics card with the nVidia Linux drivers 1.0-9746. My X11 server is version 6.8.2. Here is a screen image of this phenomenon http://msg.ucsf.edu:8100/~baucom/images/chimera_image.jpg I have rotate the model slightly to show that the thin wireframe stays behind. It is not a separate object in the model panel. Thanks Albion

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Morph Map
by Tom Goddard 07 Feb '07

07 Feb '07

I've added a Chimera extension called Morph Map http://www.cgl.ucsf.edu/chimera/experimental/morph_map/morphmap.html to the experimental features web page: http://www.cgl.ucsf.edu/chimera/experimental/experimental.html It interpolates between two volume data sets and makes animations. The original version of this tool was written by Wei Zhang in Pawel Penczek's lab. Tom

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Re: [Chimera-users] Map Orientation for Symmetry Plug-in
by Tom Goddard 07 Feb '07

07 Feb '07

Hi Albion, Ok, I made the "fit map in map" tool print out a point on the rotation axis. The new code for use with Chimera 1.2318 is here: https://www.cgl.ucsf.edu/cgi-bin/chimera-get.py?file=experimental/fitmap231… The zip file contains a directory FitMap that you put in your Chimera distribution under chimera/share or on Mac Chimera.app/Contents/Resources/share For more installation details see http://www.cgl.ucsf.edu/chimera/experimental/install.html This FitMap directory replaces your existing one. After restarting Chimera you can fit a helically symmetric map in a rotated copy of itself then get the axis point (shown in Favorites / Reply Log) and adjust the map origin (volume dialog Features / Origin and Scale) to put the axis point at (0,0,0). I described this in more detail in my previous message: http://www.cgl.ucsf.edu/pipermail/chimera-users/2007-February/001313.html The output of the axis point will be included in the next Chimera snapshot due out in one to three weeks. The matrix you sent me had no rotation, just a translation by 52 along z. You will need to rotate the map copy before fitting to get a meaningful rotation axis point. In fact I suspect the accuracy will be increased for rotations near 180 degrees rather than small rotations (e.g. 30 degrees). Tom Albion Baucom wrote: > Thanks Tom. > > OK, here is my rotation matrix after following your instructions > > 0.99944468 -0.03326699 0.00190528 -0.09024247 > 0.03326443 0.99944566 0.00136109 0.10539160 > -0.00194951 -0.00129696 0.99999726 52.82194789 > > Sorry, I forgot how to compute the rotation axis vector from this > matrix ... its been awhile since I had to do that manually ... its > pretty simple if I remember right. > > Any code to automate this would be greatly appreciated. > > Thanks again! > > Albion

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colorzone tool
by Jeff 06 Feb '07

06 Feb '07

would it be possible to allow 'color zone' to go past 30 A radius? -Jeff

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Hiding part of a marker set
by Tom Goddard 06 Feb '07

06 Feb '07

Hi Jeff, You can hide part of a marker set by selecting the markers you want to show (maybe using the select connected shortcut "sc" as described earlier) then use invert selection (main window menu Select / Invert, or shortcut "is"), then use path tracer menu entry Actions / Hide markers (or shortcut "ha" for hide atoms). Tom Jeff wrote: > I don't suppose there's a way to hide only a portion of a marker set > (just keep one filament visible out of 10, for instance) > > -Jeff

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Mac laptop benchmark
by Tom Goddard 06 Feb '07

06 Feb '07

Hi Jeff, I ran the Chimera benchmark tool on my new MacBook Pro and got scores: surface 543 mesh 545 contour 183 solid 256 recolor 132 But running hand tests I see the real surface/mesh scores should be 380. It appears the benchmark no longer is reporting correct scores either because a graphics driver optimization is speeding things up because the test image is not actually displayed, or Chimera code has changed (perhaps no longer guaranteeing the OpenGL buffers are swapped). Probably other scores on the Chimera benchmark web page are likewise inaccurate. This will have to be investigated. At any rate, actual surface rendering is about 65% faster than my Dell Precision M50. A test on a GeForce Go 7400 (aka Quadro NVS 120M) in a new Dell Lattitude D820 also gave erroneous scores, but hand testing gave surface rendering score 420 and horrible mesh (110) and solid (<20) numbers. Tom Jeff wrote: > could you run the benchmark on your mac? (I have run it on my > workstation, but forgot the scores; will do again and compare) > > -jeff

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NumPy in Chimera
by Tom Goddard 06 Feb '07

06 Feb '07

Hi Chimera Extension Writers, If you have written Chimera extensions that use Numeric Python you will need to convert them to instead use NumPy to work with future versions of Chimera. NumPy provides almost all the same routines as Numeric but some function and module names have changed. We are switching Chimera over from Numeric Python to NumPy and will have a Chimera snapshot out in one to three weeks that uses NumPy. We envision having a Chimera production release that uses NumPy in perhaps 3 months. The change was necessary because Numeric is no longer maintained. Numeric will no longer be included with Chimera because dynamic library name space collisions with NumPy occur on the Mac because of certain Chimera compilation options. The conversion of Chimera code was not much trouble, but we had to also convert third party packages that are included with Chimera (PyOpenGL, MMTK, Scientific (for netcdf file reading), MSMS molecular surfaces) and that took some work. Thanks for your patience. Tom

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Re: [Chimera-users] question about mac laptops / workstations and chimera stability
by Tom Goddard 06 Feb '07

06 Feb '07

Hi Jeff, I just got my MacBook Pro with 2 Gb memory and 160 Gb hard-drive yesterday. It's been working well with Chimera volume display, surface and solid. Performance is roughly a factor of two better than my 4 year old Dell Precision M50 with Quadro 4 GoGL 500 graphics (a very heavy machine, ~10lb). I just took a look at a 2k by 2k by 76 tomogram and performance was as expected. 2 Gb memory is adequate for my uses. I went for the 160 Gb harddrive instead of the 120 Gb since volume data and video can take some space. The 200 Gb option was a 4200 rpm drive which I suspect would be slower than the smaller 5200 rpm models so I avoided it. If you'd like to try my laptop before you order you are welcome to come over to my house in SF. Tom Jeff wrote: > Tom, > > is the base 2 GB memory sufficient, and do you have any reservations > regarding transfer speed from the harddrive? > > I am going to place an order, wanted to check with you first about > those 2 things before going ahead. > > (I figure, if you are developing on it, this is not a bad idea.) > > -Jeff

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Map Orientation for Symmetry Plug-in
by Albion Baucom 05 Feb '07

05 Feb '07

I am using the Symmetric Molecule Copies plug-in with Chimera. I am wondering if there is a preferred way to orient an EM volume so that it is centered around the z-axis at the origin. From my experience with this plug-in, symmetry related molecules are generated around z-axis at the origin of the viewing area. I am finding that my maps tend to be close, but not exactly oriented around the z-axis for a helical volume. Molecules fit into a portion of the map then tend to have slightly askew symmetry mates relative to the volume (presumably because the z-axis of the map is not exactly oriented along the origin of the symmetry z-axis). After playing around with various map tools (MAPMAN, Priism), I am still not satisfied with my orientation protocol and wonder if anyone can suggest a tried and true method for this. Thanks Albion

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Re: [Chimera-users] volume/3586 problem zoning out volume
by Thomas Goddard 05 Feb '07

05 Feb '07

Hi Jeff, To check the memory limits set by a bash shell use shell command "ulimit -a". For a csh use "limit". Here's an example on my Mac (no memory limit). Tom $ ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) 6144 file size (blocks, -f) unlimited max locked memory (kbytes, -l) unlimited max memory size (kbytes, -m) unlimited open files (-n) 256 pipe size (512 bytes, -p) 1 stack size (kbytes, -s) 8192 cpu time (seconds, -t) unlimited max user processes (-u) 100 virtual memory (kbytes, -v) unlimited Jeff wrote: > I had forgotten about 4-byte floats versus 2-byte integers, > > you are right in that this is most likely a machine limitation, I was > surprised to get a fault and error about an allocation call. is there a > specific environment variable I should check to see if the shell is > limiting chimera's memory requests, I will change that if possible (?). > > -Jeff >

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rotation by a set angle
by Eva Vanamee 05 Feb '07

05 Feb '07

Hi, I am trying to make a figure of my EM fit at different orientations. Is it possible to rotate the molecule/map by a certain angle so I know exactly the rotation between views? Thanks in advance, - Eva

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Re: [Chimera-users] not able to 'transfer markers'
by Thomas Goddard 05 Feb '07

05 Feb '07

Hi Jeff, Menu entry "Actions / Transfer selected markers to current set" in the path tracer dialog moves the markers to the marker set chosen on the first line of the path tracer dialog. That should be the same as the one chosen in the marker set scrolling list (Features / Marker set list) unless that list has multiple sets selected. The error message "Markers in one set cannot link to markers in a different set" means you tried to transfer some markers to the current set but they were connected by at least one link to markers in another set. That is not supported. There is a command, keyboard shortcut "sc" that extends the current selection to all markers connected to currently selected ones. You'll need to turn on keyboard shortcuts with main window menu entry Tools / General Controls / Accelerators On. You can have them turned on by default every time you start Chimera using the Preferences dialog (menu Favorites / Preferences) category Tools and clicking the check button in the autostart column next to "Accelerators On". One possible confusion about hiding/showing markers is that if you have any markers selected then the Actions / Show & Hide menu entries act on those selected ones no matter what marker set they belong to. If there are no markers selected then those same menu entries act on all markers in the current marker set, that is the one chosen at the top of the path tracer dialog. The marker set scrolled list is used for closing multiple marker sets and for saving multiple marker sets. This may have been the problem when you could not close a marker set. It closed the one selected in the scrolled list which was different from the "current marker set" shown at the top of the path tracer dialog. When you change the current marker set menu it unfortunately does not clear the selected marker sets in the scrolled list. That is a bug. Let me know if you can reproduce the problem hiding/showing markers. Tom Jeff wrote: > hi Tom, > > using build 2318, if I select a series of markers, and then click > 'actions -> transfer selected markers to current set', it gives the > error 'Markers not transfered. Markers in one set cannot link to markers > in a different set.' when I did this, I assumed that the 'current set' > meant the one selected in the 'marker sets' dialog box in the volume > path tracer. > > is there a way for me to get around this? I had traced out a series of > actin filaments in one set, and for practical reasons want to be able to > show/hide each marker path that corresponds to a filament; the only way > I could think of doing this was to have each filament be a separate > marker file, unless there is a command that allows me to select a single > marker and then just 'display markers connected to selected marker' > (preferred, actually), as opposed to using the up-arrow, which selects > the entire set. > > after performing the 'transfer markers' request, I was no longer able to > show/unshow the marker sets. Also, when I closed a marker set, it was > still displayed. I shut down the session and recreated it from scratch. > I'll let you know if this show/unshow/close marker file issue occurs > again and under what circumstances; it would be hard for me to claim > that it was correlated to the 'transfer markers' command, I just know > that after that point in the session I could no longer show/unshow/close > the markers. > > thanks, > > -Jeff >

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PDB file format for movie
by Mingfeng Yang 05 Feb '07

05 Feb '07

Dear Chimera users and developers, I'd like to use chimera to view the motions of a protein. If all the snapshots are to be saved in a single PDB file, what's the correct format for them? I tried the following, but chimera complained that a single structure is included only. Thanks, Mingfeng ------------------ MODEL 1 ATOM 1 N ALA 1 -4.564 -7.956 -6.531 1.00 0.00 N ATOM 2 CA ALA 1 -5.237 -8.746 -5.532 1.00 0.00 C ATOM 3 C ALA 1 -4.360 -9.172 -4.378 1.00 0.00 C ... ATOM 81 HN ALA 10 0.195 11.398 3.736 1.00 0.00 H END MODEL 2 ATOM 1 N ALA 1 -5.031 -8.234 -5.174 1.00 0.00 N .... END

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Re: [Chimera-users] question about mac laptops / workstations and chimera stability
by Thomas Goddard 05 Feb '07

05 Feb '07

Hi Jeff, I have not seen any graphics driver bug reports with the MacBook Pro with X1600 graphics. I just ordered this machine to replace my four year old Dell with Quadro 4 graphics -- I am confident it will work well using volume data in Chimera. Here is our graphics driver bug page of problems observed with Chimera http://www.cgl.ucsf.edu/chimera/graphicsbugs.html It only has about 1/3 of the driver bugs and I will be adding more from our Chimera bug tracking system when I have time. Tom

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volume path tracer / render surface with marker set
by Jeff 02 Feb '07

02 Feb '07

hello, is there a way to render a surface of arbitrary thickness using a marker set? as in, fit some sort of spline to a marker set, with the constraint being that the algorithm assumes they all lie on the same surface? this would be useful for modeling membranes, perhaps it is already implemented and I am not seeing it in the dialogs. thanks, -J

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Copying volume settings to a second data set
by Thomas Goddard 02 Feb '07

02 Feb '07

Hi Jeff, There is no capability to copy settings (thresholds, colors, brightness, display style, rendering options) that are specific to each volume data set to another data set. That would be useful and I'll add it to the feature request list. Here are some hacks to achieve this. I don't think they are worth the trouble to use but you can decide. If you save a Chimera session with a volume having settings you want to reuse you can edit the session file changing the line: 'path': 'F:\\cygwin\\home\\Tom\\work\\volume\\emd\\emd_1282.map', to 'path': 'F:\\cygwin\\home\\Tom\\work\\volume\\emd\\XXX.map', Then when you reopen that session Chimera will say it cannot find the map file and ask you to select a new map file with a file open dialog. You can choose some other map. The settings from the original map will then be applied to this newly opened map. Another hack is to use the Volume Series tool available on the experimental features web page: http://www.cgl.ucsf.edu/chimera/experimental/experimental.html You can open your maps that you want to use the same settings for as a "volume series". That tool copies settings when you use it to flip between volume in a series. It can even adjust thresholds so they have the same rank position on the histogram (e.g. greater than 94% of voxel values). Tom Jeff wrote: > thanks Tom, > > is there a way to save the thresholds (and color settings) in the > volume viewer, so that when I close a map and reopen a > similar/filtered one, I don't have to re-do all the settings > (brightness and transparency too, for instance) > > i realize the histrogram changes for each map, but even if it saved > how many control points (and their colors) were there, that would > work. is there a 'save volume viewer state' button? I could not find one. > > -Jeff >

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Question on how to represent only chain A of Chimera
by nsomboon＠berkeley.edu 02 Feb '07

02 Feb '07

Hi, I need help. I received the modeling structures of my query (black) and the best representative 1qopB (magenta) through MODWEB, and used Chimera to visualize them (please see attached file). However, the magenta structure also contains 1qopA, in which I only want the 1qopB and don't want the 1qopA. I read through tutorials but cannot find a way to get rid of the chain A of the 1qop. Hence, could you please direct me of how to cut out chain A of 1qop in this attached file? Thank you very much. Sincerely yours, Nara

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Saving modified PDB files
by Bernard Heymann 02 Feb '07

02 Feb '07

I have a problem saving PDB files relative to density maps in recent versions of Chimera. When I load a PDB file and move it relative to a density map, and then try to save it relative to the density map, it does not apply the transformation to the PDB coordinates. This used to work in older versions. My workaround is to have another molecule open and save the transformed one relative to that. However, I would prefer to be able to save a transformed molecule relative to a density map. Can this be fixed? Bernard Heymann, Research Fellow Rm 1515, 50 South Dr., MSC 8025, NIAMS, NIH Bethesda MD 20892-8025 Tel. 301-451-8241, Fax. 301-480-7629

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Chimera to visualize MOLDEN-generated VRML2.0 files
by Kalju Kahn 01 Feb '07

01 Feb '07

Dear Chimera users, I am looking for advice on how to make chimera work with VRML 2.0 files generated by MOLDEN. MOLDEN seems to generate valid VRML files (octagaplayer reads these in all right) but chimera crashes with Segmentation fault (core dumped) This happens both on 32-bit Suse 9 system and 64-bit recent Ubuntu system. Any ideas are appreciated! Kalju ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Dr. Kalju Kahn Department of Chemistry and Biochemistry University of California, Santa Barbara

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anyone using chimera on a an IBM T43p
by Jeff 01 Feb '07

01 Feb '07

hello, I have an IBM T43p (June '05 or so release) which has an ATI FireGL v3200 (Mobility). In XP, it isn't possible to try out drivers from the vendor, I am limited to drivers from IBM. In Linux, I have been able to install proprietary drivers from ATI, but there is no selection for the 'Mobility' version of the v3200 on ATI's website; the install has not complained though, and basic stuff appears to be fine (GUI is ok, glxgears, etc). In both XP and Linux, chimera will crash when attempting to use volume maps. It appears fine with pdb files, although I typically work with volume data so haven't rigorously tested that. I have been assuming that the FireGL v3200 (Mobility) is the same logic as the v3200, at least documentation I have been able to find seems to imply that. Does anyone know (or suggest) a chimera-stable driver version from ATI that I might test? I might at least be able to get it to work in Linux, as the driver suite downloaded from ATI appears to cover most late-generation cards. thanks for any suggestions, -Jeff

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Re: [Chimera-users] access to pdb parser
by Jean Didier Pie Marechal 01 Feb '07

01 Feb '07

Hi Eric, Well, the truth is that these are two good news. Most likely I didn't explain myself correctly. In reality, for practical reasons, I'd like to use only chimera for the teaching. So, I am planning to only use its internal python shell for python applications. Therefore the tips you gave me are perfect. Thanks a lot for the help! Cheers JD Dr. Jean-Didier Maréchal Professor Lector Unitat de Química Física Departament de Química Universitat Autònoma de Barcelona Edifici C.n. 08193 Cerdonyola (Barcelona) Tel: +34.935814988 e-mail: JeanDidier.Marechal(a)uab.es ----- Missatge original ----- De: Eric Pettersen <pett(a)cgl.ucsf.edu> Data: Dimecres, Gener 31, 2007 10:31 pm Assumpte: Re: [Chimera-users] access to pdb parser > Hi JD, > I have good news and I have bad news. The good news it that using > > PDBio to do what you want is pretty easy. The bad news is that you > > can't use it in a generic Python shell, only in Chimera's own > Python > shell. This is because we use a modified version of Python so that > > the types we define in the C++ layer (Molecule, etc.) can have > attributes added to them in the Python layer -- otherwise they > would > behave like the built-in Python types (dict, list. etc.) that can't > > have arbitrary attributes added to them. We intend to improve our > own code to make modifying Python unnecessary, but haven't gotten > to > it so far. > Nonetheless, you can basically use Chimera in place of a Python > interpreter. "chimera --nogui script.py" will execute the Python > script named script.py without bringing up the Chimera interface. > Also, you can start Chimera normally and bring up the graphical > interface to its interactive Python shell, IDLE (under Tools- > >General > Controls) and type Python commands to that. > Here's a session of me using PDBio in IDLE. I've added some > comments. > >>> from chimera import PDBio # import PDBio > >>> pdbio = PDBio() # create a PDBio instance > >>> mols = pdbio.readPDBfile("/mol/pdb/gc/pdb1gcn.ent") # read a > PDB file given its file name > >>> m = mols[0] # readPDBfile() returned a list of models (NMR > can > have many) so get the model itself > >>> m.pdbHeaders["HEADER"] # each model will have a pdbHeaders > dictionary, keyed by the record type, the values will be a list of > strings -- the PDB records > ['HEADER HORMONE 17-OCT-77 > 1GCN 1GCN 3'] > >>> > > --Eric > > On Jan 31, 2007, at 12:42 PM, Jean Didier Pie Marechal wrote: > > > Hi Eric, > > > > Yes, that would be better to explain more what I'd like to do. > > > > I am planning to give a practical on computational (bio)chemistry > > > in my department next year. I'd stongly like to have the students > > > using chimera and python as their main tools (though both are > tools > > I am in process of learning :-)). > > > > One of the "simple things" I have in mind, is to obtain pdb infos > > > directly from the shell e.g list the SEQRES entry or access to > the > > resolution (REMARK 2), the crystallization conditions etc. The > > students will be chemists and I think that from a didactic point > of > > view, obtaining infos from the python shell would be better that > > reading the pdb files, especially if we want to compare different > > > structures e.g. Writing a comand that gives you ALL the > resolutions > > of the 10 structures you loaded would be interesting. I looked at > > > the PDBio, but I can see how to catch REMARKS infos. > > > > I'd really like to have this work going on, but as you can see, I > > > am a bit lost in where to begin. > > > > Any help to tell me where to start would be fantastic! > > > > Cheers > > > > JD > > > > > > > > > > Dr. Jean-Didier Maréchal > > Professor Lector > > Unitat de Química Física > > Departament de Química > > Universitat Autònoma de Barcelona > > Edifici C.n. > > 08193 Cerdonyola (Barcelona) > > Tel: +34.935814988 > > e-mail: JeanDidier.Marechal(a)uab.es > > > > ----- Missatge original ----- > > De: Eric Pettersen <pett(a)cgl.ucsf.edu> > > Data: Dimarts, Gener 30, 2007 1:25 am > > Assumpte: Re: [Chimera-users] access to pdb parser > > > >> Hi JD, > >> Chimera does its PDB parsing in the C++ layer (the PDBio class in > >> > >> the Python layer). There is a file named PDB.py in the mmCIF- > >> parsing > >> module, but it's not for parsing PDB files. Perhaps if you > >> described > >> why you need Python PDB parsing I could suggest options -- using > >> PDBio possibly being one of them. > >> > >> --Eric > >> > >> Eric Pettersen > >> UCSF Computer Graphics Lab > >> pett(a)cgl.ucsf.edu > >> http://www.cgl.ucsf.edu > >> > >> On Jan 29, 2007, at 1:49 PM, Jean Didier Pie Marechal wrote: > >> > >>> Hello everyone, > >>> > >>> a short question. What is the right call for importing the > >>> pdbparser module in the chimera python shell? I found the PDB.py > >> > >>> module in the site-package mmlib, but I don't know how to import > >> it...> > >>> Thanks a lot, > >>> > >>> JD > >>> > >>> > >>> Dr. Jean-Didier Maréchal > >>> Professor Lector > >>> Unitat de Química Física > >>> Departament de Química > >>> Universitat Autònoma de Barcelona > >>> Edifici C.n. > >>> 08193 Cerdonyola (Barcelona) > >>> Tel: +34.935814988 > >>> e-mail: JeanDidier.Marechal(a)uab.es > >>> > >>> > >>> _______________________________________________ > >>> Chimera-users mailing list > >>> Chimera-users(a)cgl.ucsf.edu > >>> http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users > >> > >> > > > > > >

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TER Cards and Rainbow Colors
by Albion Baucom 31 Jan '07

31 Jan '07

Is there any way to introduce TER records between breaks in a chain, and still have N->C coloring continuous through a single chain? I have for instance a structure with missing loops that were not observed in density. Therefore there are breaks in the main chain. This is a very common occurrence. To prevent spuriously long bonds I have introduced TER records between the breaks. Then when I apply rainbow coloring from N->C terminus I get the spectral coloring between TER records rather than from the beginning of the chain to the end. I tried the card BREAK, but evidently that is not interpreted by Chimera. Coloring by chain, or by model in the Rainbow panel does not produce the desired effect. Thanks Albion

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Re: [Chimera-users] access to pdb parser
by Eric Pettersen 31 Jan '07

31 Jan '07

Hi JD, I have good news and I have bad news. The good news it that using PDBio to do what you want is pretty easy. The bad news is that you can't use it in a generic Python shell, only in Chimera's own Python shell. This is because we use a modified version of Python so that the types we define in the C++ layer (Molecule, etc.) can have attributes added to them in the Python layer -- otherwise they would behave like the built-in Python types (dict, list. etc.) that can't have arbitrary attributes added to them. We intend to improve our own code to make modifying Python unnecessary, but haven't gotten to it so far. Nonetheless, you can basically use Chimera in place of a Python interpreter. "chimera --nogui script.py" will execute the Python script named script.py without bringing up the Chimera interface. Also, you can start Chimera normally and bring up the graphical interface to its interactive Python shell, IDLE (under Tools->General Controls) and type Python commands to that. Here's a session of me using PDBio in IDLE. I've added some comments. >>> from chimera import PDBio # import PDBio >>> pdbio = PDBio() # create a PDBio instance >>> mols = pdbio.readPDBfile("/mol/pdb/gc/pdb1gcn.ent") # read a PDB file given its file name >>> m = mols[0] # readPDBfile() returned a list of models (NMR can have many) so get the model itself >>> m.pdbHeaders["HEADER"] # each model will have a pdbHeaders dictionary, keyed by the record type, the values will be a list of strings -- the PDB records ['HEADER HORMONE 17-OCT-77 1GCN 1GCN 3'] >>> --Eric On Jan 31, 2007, at 12:42 PM, Jean Didier Pie Marechal wrote: > Hi Eric, > > Yes, that would be better to explain more what I'd like to do. > > I am planning to give a practical on computational (bio)chemistry > in my department next year. I'd stongly like to have the students > using chimera and python as their main tools (though both are tools > I am in process of learning :-)). > > One of the "simple things" I have in mind, is to obtain pdb infos > directly from the shell e.g list the SEQRES entry or access to the > resolution (REMARK 2), the crystallization conditions etc. The > students will be chemists and I think that from a didactic point of > view, obtaining infos from the python shell would be better that > reading the pdb files, especially if we want to compare different > structures e.g. Writing a comand that gives you ALL the resolutions > of the 10 structures you loaded would be interesting. I looked at > the PDBio, but I can see how to catch REMARKS infos. > > I'd really like to have this work going on, but as you can see, I > am a bit lost in where to begin. > > Any help to tell me where to start would be fantastic! > > Cheers > > JD > > > > > Dr. Jean-Didier Maréchal > Professor Lector > Unitat de Química Física > Departament de Química > Universitat Autònoma de Barcelona > Edifici C.n. > 08193 Cerdonyola (Barcelona) > Tel: +34.935814988 > e-mail: JeanDidier.Marechal(a)uab.es > > ----- Missatge original ----- > De: Eric Pettersen <pett(a)cgl.ucsf.edu> > Data: Dimarts, Gener 30, 2007 1:25 am > Assumpte: Re: [Chimera-users] access to pdb parser > >> Hi JD, >> Chimera does its PDB parsing in the C++ layer (the PDBio class in >> >> the Python layer). There is a file named PDB.py in the mmCIF- >> parsing >> module, but it's not for parsing PDB files. Perhaps if you >> described >> why you need Python PDB parsing I could suggest options -- using >> PDBio possibly being one of them. >> >> --Eric >> >> Eric Pettersen >> UCSF Computer Graphics Lab >> pett(a)cgl.ucsf.edu >> http://www.cgl.ucsf.edu >> >> On Jan 29, 2007, at 1:49 PM, Jean Didier Pie Marechal wrote: >> >>> Hello everyone, >>> >>> a short question. What is the right call for importing the >>> pdbparser module in the chimera python shell? I found the PDB.py >> >>> module in the site-package mmlib, but I don't know how to import >> it...> >>> Thanks a lot, >>> >>> JD >>> >>> >>> Dr. Jean-Didier Maréchal >>> Professor Lector >>> Unitat de Química Física >>> Departament de Química >>> Universitat Autònoma de Barcelona >>> Edifici C.n. >>> 08193 Cerdonyola (Barcelona) >>> Tel: +34.935814988 >>> e-mail: JeanDidier.Marechal(a)uab.es >>> >>> >>> _______________________________________________ >>> Chimera-users mailing list >>> Chimera-users(a)cgl.ucsf.edu >>> http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users >> >> > >

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Re: [Chimera-users] Update volume display without pressing show
by Thomas Goddard 31 Jan '07

31 Jan '07

Hi Jeff, I also wasn't able to reproduce this problem. There is probably a real problem but some step that causes it is missing. If you figure out that step let me know. Tom Jeff wrote: > sorry about the confusion, > > what I meant by 'does not work', is that once I have loaded the volume > planes tool, it appears to not allow me to select 'update display > without pressing show'. (the button is depressed in the dialog box, or > i unclick/reclick it, but it no longer toggles 'update....w/o press > show' on and off). 2318 build. > > sequence: > > 1) load map; display with solid rendering. default is 'update w/o > press show', and you can see the effect of playing with histogram > update in realtime. > > 2) start volume planes. now requires me to press 'show' to update the > display. this also includes other volumes that vol planes is not used > on, and 'update w/o show' no longer works in surface or solid mode. > > 3) close volume planes, or close session. problem persists. > > 4) restart chimera, now it allows 'update..w/o press show' again. > > so, this happened to me twice, and i figured it was just something to > do with the volume planes tool. As I am writing this, I just re-did > the sequence above, and now it works (volume plane tool updates, can > switch to surface). Because I can no longer replicate this, I should > probably be ignored. Also, I just loaded one of the sessions I was > having a problem with into a new launch of chimera, thinking there > might be some sort of 'system/state snapshot' I could send you, but > now it is working too. So, it appears to have been fixed by a restart > of chimera. Again, please ignore. > > -Jeff

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Re: [Chimera-users] Update volume display without pressing show
by Thomas Goddard 31 Jan '07

31 Jan '07

Hi Jeff, I tried the volume "update show" option in combination with volume planes and did not find an problem. Can you give me step by step instructions to produce the problem? Also I don't know what you mean by "does not work". Does it always update automatically, or never update automatically? What Chimera version? With the volume planes tool, the full map is still opened -- it is just display a subregion that is 1 plane high. Use Features / Region Bounds to see and change the subregion. Or use Features / Subregion Selection and press the Full button to get back to the full map. Also the volume planes dialog always acts on the volume displayed in the volume dialog. Perhaps it should have its own menu to choose the volume you want to show planes for. Tom Jeff wrote: > even if I close the volume planes tool, > > 'update display without pressing Show' no longer works (for instance, > adjusting the volume rendering histogram, or clicking 'surface' > rendering). if I close, then re-open the volume, it still doesn't > work. bug, or my version maybe? > > also, once you start 'volume planes tool', it only keeps track of the > plane it has pulled from the volume map - what used to be a > 100x100x100 volume is now 100x100x1; the volume viewer 'renames' the > map but does not save it out that way (which is good). is there a way > to be able to keep the full volume around, but not displayed? there > are reasons you might want to do that (well, I found myself trying to > do that), without having to re-open the volume. > > i did check to see if i could open 2 copies - one first to run 'volume > planes' on, and then one to subsample but have as a volume rendering, > for example. this works, as long as i don't accidentally touch the > 'volume planes' dialog when fooling with the second opened copy of the > volume. > > mainly just curious, not asking for additional functionality, just > wanted to let you know what I was trying and why. > > -Jeff > > > > Thomas Goddard wrote: >> Hi Jeff, >> >> The volume dialog data display option "Update display without >> pressing Show" only effect volume dialog features. It does not have >> any effect on the Volume Planes tool. The Volume Planes tool does >> not allow adjusting the plane number without updating the display. >> >> Tom >> >> >> Jeff wrote: >>> hi Tom, >>> >>> I have volume planes and precomputed subsamplings going, and the >>> 'update display without pressing Show' no longer works (keep >>> toggling on and off, but it doesn't have an effect) >>> >>> is there a way for me to 'refresh' the state of buttons like that? >>> >>> -Jeff >>

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Watershed segmentation of volumes
by Thomas Goddard 31 Jan '07

31 Jan '07

Hi Jeff, There is no watershed or flood-fill type of method in Chimera for segmenting volume data. This is on our (very long) list of features to develop though. Tom Jeff wrote: > tom, > > i hate to keep piling on questions, but how hard would it be to have a > feature where one places a chimera marker, and then has some sort of > algorithm expand to 'fill' the space, kind of an isosurface problem > (or does this already exist) > > i have 'voids' in some of my maps (stained sections) which i think > correspond to protein, like one sees in negative stain (the positive > values/density in the map correspond to stain; an enclosed void > (density more or less = 0 or close to it) is thought to represent the > actual protein, which was covered in stain, kind of like 'magic shell' > on ice cream - or think of dairy queen cone, dipped in chocolate that > then solidifies), and would like some way to 'grow' a blob in the void > (or at least try) > > does this already exist? i have a buddy who does level set methods who > is often looking for ways to use his library, but i thought i should > ask you first if there is some functionality like this > > -jeff

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Quadro FX 1400/3450 performance
by Thomas Goddard 31 Jan '07

31 Jan '07

Hi Maya, It must be exciting and alot of work to get your lab running. Glad to hear you are making Chimera converts. Graphics benchmark scores using Chimera with the quadro fx 1400 and quadro fx 3400 are shown here http://www.cgl.ucsf.edu/chimera/benchmarks.html We don't have any numbers for the fx 3450 and I don't know if it is similar to the 3400. The 1400 and 3400 have very similar Chimera scores. The Chimera scores indicate how big a test volume can be handled at 10 frames per second. Both these cards are very fast. The one difference I see is that on the Nvidia web site they say the 1400 has 128 Mbytes of memory while the 3450 has 256 Mbytes. http://www.nvidia.com/page/qfx_mr.html http://www.nvidia.com/page/quadrofx.html (fx 3400) Maybe that info is out of date -- maybe there is a choice of memory size. On the Chimera page the fx 1400 had 256 Mb. And 128 Mbytes is small by today's standards. 256 Mbytes is common, and 512 Mbytes is available with some cards. The amount of graphics memory is most noticable if you use the Chimera "solid" rendering mode because it tries to put red,green,blue 8-bit values for the entire volume on the card. For 256^3 volume that is 48 Mbytes, or if you use Chimera 2-D textures mode (the default) it take 3 times that (144 Mbytes). It can also make a difference for very large contour surfaces -- ones you might use for making a figure but would be too slow for interactive rotating (e.g. 10 million triangles at about 18 bytes per triangle = 180 Mbytes). Regarding stereo, I'm not sure if there are any flat panel displays that can work with the LCD glasses. They don't refresh fast enough so there is too much flicker. So you either need a CRT display or maybe some special high-end flat panel. See you at the EMAN workshop. Maya Topf wrote: > Hi Tom, > > How are you? > I am slowly settling down in the UK. Lots of work and collaborations. > A few people from the EM group at birkbeck started using chimera and > they really like it! > > I have a question about graphics cards and maybe you can help me. > I am thinking about buying either NVIDIA QUADRO FX 1400 (stereo) or FX > 3450 (stereo). > Do you think that there is a big difference when I want > to visualise large maps with chimera for example? > > thanks, > Maya > > I saw that you are coming to the eman workshop so I guess I will see > you there! > Tom

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ViewDock descriptors problem
by "Воронков андрей" 31 Jan '07

31 Jan '07

Dear Chimera users, I have ranked database from DOCK. I need to see energies of these structures and their ranking. I open them by View Dock, but in the field Column menu I can see only name field. Why I don't have energy field there and how can I get it? Respectively yours, Andrew PS "Descriptors can be shown in or removed from the upper panel using the Column menu." -this is from manual, but I can;t make shown any descriptos but the name of the structure

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Re: [Chimera-users] using a marker file to zone a volume from python prompt
by Thomas Goddard 30 Jan '07

30 Jan '07

Hi Jeff, I added a user interface dialog for rotating and translating atom coordinates. Markers in Chimera are equivalent to atoms so it works on those. The rotation is specified in Euler angles. The new dialog, called Transform Molecule Coordinates, is available on the experimental features web page: http://www.cgl.ucsf.edu/chimera/experimental/experimental.html Tom Jeff wrote: > thanks Tom, > > much appreciated. how hard is it for me to write a dialog GUI to provide > 3 numerical inputs to the rotation script you forwarded me? (is it more > involved than a few lines? I am not familiar with Tkinter). > > don't want to bother you too much, if it is not a quick thing/response > feel free to punt, please. > > -jeff >

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Update volume display without pressing show
by Thomas Goddard 30 Jan '07

30 Jan '07

Hi Jeff, The volume dialog data display option "Update display without pressing Show" only effect volume dialog features. It does not have any effect on the Volume Planes tool. The Volume Planes tool does not allow adjusting the plane number without updating the display. Tom Jeff wrote: > hi Tom, > > I have volume planes and precomputed subsamplings going, and the 'update > display without pressing Show' no longer works (keep toggling on and > off, but it doesn't have an effect) > > is there a way for me to 'refresh' the state of buttons like that? > > -Jeff

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Re: [Chimera-users] Representation of volume data in memory
by Thomas Goddard 30 Jan '07

30 Jan '07

Hi Jeff, I suspect 2-byte integers are not faster to access or compute with then 4-byte floats on modern CPUs. But more of the map will fit into the CPUs cache which could improve bandwidth and could make computing a contour surface faster. But I don't think that will be significant. You would need to test it to know. Chimera keeps the native data type of the map to conserve memory when reading large maps. Tom Jeff wrote: > does this mean that a 2-byte integer format of a file will display > faster / render triangles faster than the equivalent sized 4-byte float > map? > > Thomas Goddard wrote: >> Hi Jeff, >> >> Chimera keeps volume data in memory using the same numeric value >> types that are present in the file, for example, 32-bit float, 16-bit >> integer, 8-bit integer. >> >> Volume data is copied only when necessary -- for instance, using the >> Gaussian Filter tool creates a floating point copy of the data since >> Gaussian convolution of integer data produces a floating point result. >> >> Tom >> >> >> Jeff wrote: >>> does chimera store all values as float internally (even if the >>> original map is in 2 byte integers), making the mode of the MRC file >>> irrelevant to chimera's performance? >>> >>> -jeff >>

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Re: [Chimera-users] zone tool and volume rendering
by Thomas Goddard 30 Jan '07

30 Jan '07

Hi Jeff, The Chimera handling of the MRC file origin position is done in Python code chimera/share/VolumeData/mrc/mrc_format.py In summary, if it is an MRC2000 file (ie has xorigin, yorigin, and zorigin header values) then (xorigin, yorigin, zorigin) is used as the xyz coordinates of the volume index (0,0,0) unless xorigin, yorigin and zorigin are all zero in which case the xyz position of the map index (0,0,0) is calculated using integer (ncstart, nrstart, nsstart) header values times the grid spacing (defined by (xlen/mx,ylen/my,zlen/mz)). It is never the case that both (ncstart,nrstart,nsstart) and (xorigin,yorigin,zorigin) are used in positioning the map. Tom Jeff wrote: > > I often use another tool to cut out subregions, that I then load into > chimera - until you told me recently, I did not know I could pre-load > subsampled maps, or be able to keep a 'subsampled overview' present > while selecting various regions > > when using other tools to cut out these smaller areas (either IMOD or > Priism), some tools record displacements, and some don't. the Priism > 'CopyRegion' tool appears to do this by adjusting the 'start pixel' > field in the MRC header. IMOD doesn't do this. the 'copyRegion' tool > also doesn't appear to transfer well to chimera, at least in my test > case the original and subvolume do not register properly. (I don't have > any expectation that it would work properly, but I would adapt if I knew > what chimera expects.) > > I am also not sure what entries chimera uses to keep track of > displacements when it cuts out volumes (I could do that experiment right > now), whether it uses 'start pixel' or 'origin', if 'origin' is recorded > in Angstroms or pixels, etc. Also, I don't know what chimera considers > the origin of a density map - if 'start pixel' is 10,10,10, the map is > 20x20x20 pixels in dim, and the origin is (0,0,0), is the origin at the > center of the map, or at the 0,0,0 pixel coordinate of the map? I have > been assuming that 'origin' has to refer to the map's origin location in > space, but this requires defining where the origin is in the volume map > (I think). if there is a 'start pixel' entry, does this effectively > shift the origin? As an example, if the pixel res is 10 A, will the map > example above now display starting at (10 A, 10 A, 10 A)? Or, is one > (or both) of these entries ignored? Finally, if there is already an > entry in one of these fields, does chimera respect that and just > increment, or does it clobber it with the relative displacement > calculated when excising a subvolume? (this slew of questions is > probably covered by a single answer, but I thought it would be good to > elaborate) > > If I knew, I could more appropriately jump between programs. As I am > writing this, I just got an email from David at Boulder telling me that > IMOD uses the origin entries in the header (but don't know yet what it > considers to be the origin, 'far left' corner or center or something else). > > -Jeff

1 0

Precomputing subsampled map sizes
by Thomas Goddard 30 Jan '07

30 Jan '07

Hi Jeff, Yes, Chimera will complain and not allow precomputed volume subsamples if the size of the subsample grid is not what is expected. In the case you give (1434,1434,110) with subsample grid of size (358,358,26) the subsample grid size is not acceptable. Notice that 4 times the subsample size is (1432, 1432, 104) So a half size bins in the first two dimensions are left off (1434 - 1432 = 2) -- that is fine. But the third dimension is missing 1.5 bins (110 - 104 = 6). The subsample file should have size 27 in the third dimension, ie (358,358,27). I don't know why squeezevol from IMOD dropped off more than a whole bin in the third dimension. Chimera allows fractional bins to be dropped off, but does not allow whole bins to be missing. Tom Jeff wrote: > hi again, > > is there a problem with the precomputed subsamplings needing even > dimensions (I pre-cut my volume to even dimensions so that a binning of > 2 would result in a whole number for the subsampled dimensions, but it > can be hard to do this for a factor of 8 in advance). > > chimera is complaining to me about bad dimensions ('Data foo.mrc of size > (358,358,26) not a valid size for dubsamples of foo.mrc of size > (1434,1434,110). > > is there a program you use to bin / get around this problem? I use > 'squeezevol' from IMOD, I am not sure if it is completely transparent in > its output for what chimera would expect > > -j

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Representation of volume data in memory
by Thomas Goddard 30 Jan '07

30 Jan '07

Hi Jeff, Chimera keeps volume data in memory using the same numeric value types that are present in the file, for example, 32-bit float, 16-bit integer, 8-bit integer. Volume data is copied only when necessary -- for instance, using the Gaussian Filter tool creates a floating point copy of the data since Gaussian convolution of integer data produces a floating point result. Tom Jeff wrote: > does chimera store all values as float internally (even if the original > map is in 2 byte integers), making the mode of the MRC file irrelevant > to chimera's performance? > > -jeff

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