- Chimera-users - RBVI Mailing Lists

orientation matrix
by Miguel Ortiz Lombardía 31 Oct '04

31 Oct '04

Hi all, Sorry, this question may be very simple, but I didn't manage to find an answer in the documentation. Is it possible to read a transformation (rotation + translation) matrix so that the molecule is displayed exactly in the orientation you wish? Thank you! Miguel -- University of York Structural Biology Lab email: mol1(a)york.ac.uk http://www.ysbl.york.ac.uk/~mol ----------------------------------------------------------------------- Et ainsi ne pouvant faire que ce qui est juste fût fort, on a fait que ce qui est fort fût juste. Blaise Pascal, Pensées

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Chimera production release
by Eric Pettersen 21 Oct '04

21 Oct '04

We have now made a production release, version 1.2038, that corrects a few problems in the 1.2029 snapshot and adds a tiny number of new features. The salient new features that weren't in the 1.2029 snapshot are: Actions...Label now allows much more flexible labeling of residues Per-Model Clipping now allows a model's clip plane to be aligned with the clip plane of another model, and allows a clip plane to be flipped 180 degrees. The 1.2029 bug fixes are explicitly listed in the 1.2038 release notes: http://www.cgl.ucsf.edu/chimera/docs/relnotes/1.2038.html Eric Pettersen UCSF Computer Graphics Lab pett(a)cgl.ucsf.edu http://www.cgl.ucsf.edu

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Re: [Chimera-users] Specifying residue color of residues with a text file
by Elaine Meng 20 Oct '04

20 Oct '04

Hi David, You can specify residues and corresponding R,G,B values using Define Attribute, which is included in our newer releases (snapshot 1.2029 and production release 1.2038, of which I recommend the latter). Basically, this tool reads a file that specifies the residues and the associated values. The manual page for Define Attribute can be viewed at: http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/defineattrib/defin… including three examples near the end: http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/defineattrib/defin… There are two general approaches you may want to consider: (1) the direct approach that you described. Just reassign R,G,B values to the existing attribute of atom color and/or residue ribbonColor. This is most like the third example, except that you would use residue specifications by number (e.g., :12.A) instead of name, and the color specifications would be in the form of R G B (e.g., 1.0 0.2 1.0) instead of color names. (2) a less direct approach but one that provides more flexibility in how you show the data. Create your own new attribute (as in the first example). Then, you can use Render by Attribute (http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/render/render.html) to show these values with colors, atom radii, and/or "worm" radii. The data will show as a histogram, and the mapping to colors and radii can be controlled with markers you place on the histogram. This may be a lot to digest, so please feel free to contact us with any further questions/issues. Thanks, Elaine ------------------- Elaine C. Meng, Ph.D. meng(a)cgl.ucsf.edu 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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[Chimera-users] Specifying residue color of residues with a text file
by David Piper 20 Oct '04

20 Oct '04

Chimera, Is it possible to provide a color input file that would include a residue number and an [R,G,B] value to color each residue in a structure? Or does one simply have to select each residue seperately within the program and specify an [R,G,B] value? For example, I would like to map some experimentally measured, functional data onto a model structure by coding it into a color. Would be much easier to use a lookup table of values than click and set each one. Thanks, David

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new Chimera snapshot release
by Eric Pettersen 20 Oct '04

20 Oct '04

Hi all, A new Chimera snapshot release (version 1.2029) is now available for download. I've summarized the major changes since the last release (1.1951) below. A list of _all_ the changes since the last release is in the release notes: http://www.cgl.ucsf.edu/chimera/docs/relnotes/1.2029.html Eric Pettersen UCSF Computer Graphics Lab pett at cgl.ucsf.edu http://www.cgl.ucsf.edu General changes --------------- The "web fetch" part of the "File...Open" dialog has been split off into its own "Fetch by ID" dialog. The Fetch dialog now supports fetching NDB IDs. Labels are now offset in the viewing coordinate system (rather than the model coordinate system), making them much less likely to be obscured. Moved C3' off of ribbon backbone so that the sugar ring isn't distorted. New Tools --------- Nucleotides (Graphics): create various nucleotide-specific depictions, such as stylized representations of base pairings or filled sugar rings Define Attribute (Utilities, Programming): assign values to new or existing attributes of atoms, residues, or models. Particularly useful in conjunction with the Render by Attribute tool. Tool Changes ------------ AddH improved to avoid steric clashes (and appears in model panel) Match -> Align can handle circular permutations in multiple alignments [formerly only in pairwise] Movie can read PSF/DCD files from CHARMM, NAMD, and X-PLOR; can read PDB-format trajectories (single concatenated file or one file per frame) Multalign Viewer can save a subset of an alignment to a file Multiscale Models includes the zone-selection options Near and Contacts PipesAndPlanks now connects the secondary structure elements with loops Web Data preference category renamed to Web Access and includes HTTP proxy options Render by Attribute implements Radii section (atom radius scales with attribute value) and Worms section ("worm" ribbon radius scales with attribute value) Ribbon Style Editor scalings are now treated similarly to cross sections (per-residue, no startup default except in New Molecules preferences); new "residue class" tab allows specification of which atoms should guide the ribbon, this generalizing ribbons to polymers other than standard peptides and nucleic acids ViewDock includes new interface for choosing compounds by descriptor values New Commands ------------ addaa: add amino acids to the C-terminus of a peptide/protein addh: add hydrogens (command implementation of AddH) bond/~bond: create and delete bonds chirality: report the R/S configuration of a chiral center (see User's Guide for caveats) defattr: define a new attribute and/or assign attribute values (command implementation of Define Attribute) rangecolor: color over a range according to attribute values rmsd: evaluate the RMSD between specified sets of atoms (without matching) Command Changes --------------- atom specification operators added for union (|) and negation (~) [previously just intersection (&) and operators for combining attributes] hbonds has "tilde version" (~hbonds) which removes the pseudobonds showing hydrogen bonds labelopt info has "res" or "residue" keyword indicating that only residue name and number should be shown (not atom name) rainbow can color by model (previously only by residue or chain); likewise for Rainbow tool select has "up" or "down" arguments which behave like up-arrow and down-arrow to broaden and narrow a pre-existing selection

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Help, chimera keeps crashing on startup
by Ann Mullin 19 Oct '04

19 Oct '04

Hi, I run Chimera on MacOS 10.3 with X11. Today I started having problems with Chimera crashing on startup. I deleted the programs and downloaded them again. No help. I reinstalled X11. Again no help. Thanks for all help. Ann Mullin Research Scientist Cell and Molecular Biology Dept. Tulane University New Orleans, LA 70118-5698 504-865-6742 (Ph) 504-865-6785 (FAX) amullin(a)tulane.edu

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by Dr .Julio Ortiz 13 Oct '04

13 Oct '04

Dear Srs: I am a new user of Chimera, and I really like it! I would like to know if some of the developers could include a new format for density maps amongs those that are readable in Chimera: EM format. That would increase its use in our group, because now we need convert our density maps to mrc each time that we want to use Chimera. With my actual skills in programming, to write a plugin will take me like a year, and I think that should be relative easy for someone with experience. As attachment I am sending a text file with a procedure wrote in matlab to read EM format files. The syntax should not be so different from python. I could also provide you with test data. Thank you very much for your help, Dr. Julio Ortiz -- Max-Planck Institut für Biochemie Abteilung Molekulare Strukturbiologie Am Klopferspitz 18 D-82152 Martinsried Germany Tel: +49 (89) 8578 2034 fax: +49 (89) 8578 2641 --------------------------------------------------------------------- This message was sent using https://webmail.biochem.mpg.de If you encounter any problems please report to rz-linux(a)biochem.mpg.de

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[Chimera-users] Re: streaks in Chimera image of virus electron density map
by Thomas Goddard 12 Oct '04

12 Oct '04

Hi Lu, The streaks on your Chimera density map display are very likely a driver bug specific to the Mac ATI Radeon 9600 Pro (RV350, 64 Mb). You don't see the streaks on a Mac with Radeon 9600 XT graphics (RV360, 128 Mb), and I don't see them with your data set on my Mac Radeon 9800 Pro (R350, 128 Mb). Setting the transparency to a non-zero value makes the streaks go away. When you use transparency Chimera does not use OpenGL display lists. This suggests that the graphics driver bug is related to display lists. OpenGL is an industry standard 3D graphics library that Chimera uses. We have had alot of graphics driver problems with Apple. We submit bug reports to them and sometimes visit them in Cupertino, but it is unlikely we could get this fixed since it appears to be limited to a graphics card they no longer sell. If the streaks do not bother you on-screen too much, a reasonable work-around might be to set transparency to 0.001 just when saving an image. This setting will substantially slow down rotation of the model so it is best to leave the transparency at 0 until you get the right orientation for image saving. Thanks for reporting the problem. Tom > Date: Tue, 12 Oct 2004 14:23:37 -0700 > From: Lu <lugan(a)scripps.edu> > To: Thomas Goddard <goddard(a)cgl.ucsf.edu> > Subject: Re: streaks in Chimera image of virus electron density map > > Hi Tom, > I see definitely see streaks in the Chimera display, and they appear to be > parallel to the one of the crystal lattices. They remain even if I rotate > the particle. When I loaded a .pdb with axis coordinates, they appear > parallel with the Y-axis. Another phenotype is that if I make the > transparency non-zero, the streaks go away. > The graphics card is an ATI Radeon 9600 Pro, 64mb. We don't notice this > problem on our other G5, which has an ATI RV360 chip with 128MB of RAM. So > there's a possibility that either our video card is bad, or that specific > ATI model has some issues. > I've attached an example map (which is a low resolution crystal structure > by the way) of our virus particle. It's dsn6/omap formatted. > I hope the problem is just isolated to our video card. > Thanks. > > -Lu > > On Tue, 12 Oct 2004, Thomas Goddard wrote: > > > Hi Lu, > > > > I took a look at the virus EM map image you sent to Eric Pettersen. > > I haven't seen this bug in Chimera. Do you see the streaks in the > > Chimera graphics window? Or do they only appear in the saved image? > > If they appear in the graphics window are they features that persist > > when the model is rotated? Also are the streaks parallel the data set > > x, y, or z axis? You could see this by displaying the outline box > > around the map with volume viewer / options / show outline box. > > > > I have the same Mac as you only my RV350 has 128 Mb. Do you happen > > to know what model graphics card you have, for example, mine is Radeon > > 9800 Pro? I don't think you can find this out from Mac OS -- you just > > have to know from when the machine was purchased. > > > > I suspect our latest Chimera snapshot release 2029 that just came > > out will exhibit the same problem. But it might be worth trying it. > > > > Can you reproduce the streaks with any small data set that I could > > get from you (by web, ftp, or email)? > > > > Hopefully we'll be able to figure this out quickly. > > > > Tom > >

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Re: [Chimera-users] display vectors
by Eric Pettersen 11 Oct '04

11 Oct '04

On Oct 11, 2004, at 6:50 AM, Mingfeng Yang wrote: > I want to show motions of some atoms. Is it possible to draw vectors > origin from each atoms in Chimera? Specifically, I like to draw an > arrow, originning from each atom, with direction and length to > describe the motion. The answer is yes, though the process is a little involved. Can I ask you in what context you are doing this? Is it related to an MD trajectory? Perhaps in future releases we could make this easier if we know specifically what you want to do and what data you are working from. Anyway, there are two methods I can suggest: VRML and pseudobonds. You can show exactly what you want with VRML, but it may be more effort. Pseudobonds may be easier, but you can’t have arrowheads. For VRML, you just compose a VRML file using a cylinder and cone for each arrow. The cone is the “arrowhead” and you have the cylinder go from the atom to the base of the cone, and have the cone point in the right direction. If you don’t know how to use VRML, this page has a spec and examples: http://www.web3d.org/x3d/specifications/vrml/ISO_IEC_14772-All/ index.html For pseudobonds, you would make up a fake molecule where the “atoms” are at the ends of the vectors you want to show. If you make a PDB file, start it with a TER card and use HETATM records for each atom, with a different residue number for each. This will ensure that Chimera won’t connect any of the atoms in the fake molecule. You can then use the PBReader tool (in the Utilities category) to read in the pseudobonds to display (including colors and optional labels). You can use the pseudobond panel (under inspectors) to control if the pseudobonds are wires or sticks, if they are dashed [wire only], and so forth. Let me know if you need any more help getting started with this. Eric Pettersen UCSF Computer Graphics Lab pett(a)cgl.ucsf.edu http://www.cgl.ucsf.edu

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[Chimera-users] streaks in Chimera image of virus electron density map
by Lu 11 Oct '04

11 Oct '04

Hello, I've been using Chimera to generate beautiful images of entire virus particle from an O-style map file. However, most of the images that I capture have a few black streaks in the image. The streaks appear as thin, parallel lines, like someone dragged a pen across a painting before it dried. Does anyone know how I can remove these streaks without having to resort to Photoshop? I can provide sample images too. Thanks in advance! -Lu Gan

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