- Chimera-users - RBVI Mailing Lists

Virus map density versus radius
by Tom Goddard 02 Mar '07

02 Mar '07

Hi Padma, I added a Chimera keyboard shortcut "rd" that prints out average map density versus radius. https://www.cgl.ucsf.edu/cgi-bin/chimera-get.py?file=experimental/radialden… This zip file contains a directory RadialDensity that you put in chimera/share. You enable keyboard shortcuts with Tools / General Controls / Accelerators On, open your VIPER map and type shortcut "rd". A table of radius and average density values is displayed in the Chimera reply log. You can copy and paste it to a plotting program. I've attached an example image for em_1sva. I used the following plotting program on the Mac. http://www.apple.com/downloads/macosx/math_science/plot.html The calculation is very slow because it is done in Python. For em_1sva (size 72^3) it took 12 seconds on my intel Mac and for em_1011 (size 256^3) it took 10 minutes. It could be 100 to 1000 times faster in C++ but that would require more code. I tested with Chimera 1.2343. I will be at the Biophysical Society meeting Sunday through Tuesday and probably not answering email. Tom Padmaja Natarajan wrote: > Tom, > > I was also wondering if it is possible to get "max. radius" value for > every entry by > radially averaging the density values for radii going in steps of the > pixel size of that map. > Then we do not have to give the radius value in the input text file > and also will be able to produce a text > file with "radius vs. average density" for each entry. Just a thought. > > Thanks > Padma >

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Fitting and measuring lengths in volume data
by Tom Goddard 02 Mar '07

02 Mar '07

Hi Mazdak, To fit a PDB model in a map in Chimera you can hand place the model in roughly the right location and then do a computational optimization that maximizes the density at the atom positions. Here are instructions: http://www.cgl.ucsf.edu/chimera/tutorials/volumetour/volumetour.html#fitmod… Your map grid plane spacing has to be set correctly in Angstroms since the PDB model coordinates are in Angstroms. Adjust the map grid plane spacing using the volume dialog menu entry Features / Origin and Scale and change the Voxel Size entry fields and press the Enter key to use those new values. Voxel size is the same as grid plane spacing. You can measure the length between two markers. Just select the link (ctrl click on it with the left mouse button) and use keyboard shortcut "pl". You first have to turn on keyboard shortcuts using menu entry Tools / General Controls / Accelerators On. Here are more details http://www.cgl.ucsf.edu/chimera/tutorials/volumetour/volumetour.html#pathle… For more info on volume data capabilities look at the Guide to Volume Data Display http://www.cgl.ucsf.edu/chimera/tutorials/volumetour/volumetour.html I will look at map merging today if I have time. So far I have been busy all week. Tom Mazdak Radjainia wrote: > Hi Tom, > > There are actually two more tasks where I was hoping that chimera could help > me. > > 1. I would like to fit high resolution data from a coordinate file in a > low-electron density map. Can chimera perform such a docking/fitting? I > tried to do it manually but I couldn't resize the opened pdb file towards my > .mrc electron density map. > > 2. Is it possible to measure the length of a link between two markers? I > tried to use the experimental "distance to surface" feature. But it never > measures the distance between two markers which I hoped it could do. > > I really appreciate that you are already helping me out with map-merging > feature which I hope doesn't cause too much trouble. It's just great to know > if I could do the entire molecular visualization and structure analysis in > chimera? > > Cheers > Mazdak >

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Re: [Chimera-users] yet another chimera question...
by Eric Pettersen 01 Mar '07

01 Mar '07

> On Jan 19, 2007, at 11:13 AM, Elaine Meng wrote: > > > One other thing you might not know is that you can save multiple > > positions in a single session (i.e. you don't have to save a session > > for each position). Positions are named/saved with the command > > "savepos" and reapplied with "reset": > > http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/savepos.html > > http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/reset.html > > > > These positions definitely include the global clipping plane > > positions. > > I'm not sure about the per-model clipping plane positions. > > They unfortunately do not contain the per-model clip planes yet. > > --Eric I have just added the saving of per-model clipping settings in positions, so it will be in the next snapshot release. A consequence of this improvement is that you will be able to use the 'reset' command to smoothly interpolate per-model clipping in scripts. --Eric Eric Pettersen UCSF Computer Graphics Lab pett(a)cgl.ucsf.edu http://www.cgl.ucsf.edu

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Re: [Chimera-users] 2d labels in chimera
by Elaine Meng 01 Mar '07

01 Mar '07

Hi Eman, We were able to restore your session and save images that included the labels (nice figure, by the way!). I will send you the resulting images in a separate message. It is now sounding like an issue with your graphics hardware and/or drivers. We would like to get information on your graphics setup - the easiest way is to choose Help... Report a Bug from the Chimera menu, which will fill in that information automatically, and send us a bug report. Since we've been trading mails, you don't need to put a lot of additional information in there, maybe just your e-mail address and something like "2d labels not included in saved image". If it is a graphics driver issue, there is not much we can do, but you may be able to improve performance by updating it. Also, we could add the information to our list of known graphics driver bugs. Thanks and sorry for the difficulties, 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 On Mar 1, 2007, at 5:50 AM, Eman Ghanem wrote: > Hi Elaine: > I e-mailed you last night and mentioned that the chimera 2d labels > are fine now. After that, I started working on a different file and > the I had the same problem (2dlabels not showing in the image > file). I am not sure where the problem is. I hope this is OK, but > I am attaching the session file including the labels Would you > please try to save is and see you have the same problem? Also, you > asked if I tried different image formats; I tried but the file type > does not make a different. Thank you. > Regards, > > Eman

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2d labels in chimera
by Eman Ghanem 28 Feb '07

28 Feb '07

Hi: I am not able to save an image that contains 2d labels as a Tiff file. Every time I save it, the labels don't show up on the image. I read on your web site that this only happens if I am trying to save an image that is smaller than the original pixels of the chimera window. However, I tried saving it without changing any specifications. Any idea what I can do?? thanks, EG --------------------------------- Don't get soaked. Take a quick peak at the forecast with theYahoo! Search weather shortcut.

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64-bit Linux chimera snapshot available
by Greg Couch 27 Feb '07

27 Feb '07

If you are running a 64-bit version of Linux with an AMD64, Opteron, or Intel Xeon processors, then please try out our new snapshot at <http://www.cgl.ucsf.edu/chimera/download.html>. This platform is now supported and will have future snapshot and production releases. Greg Couch UCSF Computer Graphics Lab

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Re: [Chimera-users] Saving model positions
by Tom Goddard 27 Feb '07

27 Feb '07

Hi Christopher, If you have 10 models open in a Chimera session and you close model number 7, the session should still save correctly. If it doesn't please report it as a bug. Unfortunately restoring the session file uses different model numbers for the density maps (the lowest available numbers). That is a bug that I need to fix. It should use all of the original model numbers even if there are gaps. Even though the model numbers will change, the orientations of all the models 1-6 and 8-10 will all be correct in the restored session. I sent your earlier email to our Chimera users mailing list. That is why your reply to me went to that mailing list. I like to post the questions to the mailing list so others can benefit from the answer and I remove any confidential information (email, phone, signature line, research details). Let me know if you want to keep your questions off of the Chimera mailing list. Here's the message where I posted your original question and my reply. http://www.cgl.ucsf.edu/pipermail/chimera-users/2007-February/001366.html Tom Christopher Akey wrote: > > Thomas - > > This went via reply to some kinda list, sorry. > > I will try some of these approaches. However, there is a question. If > you have 10 objects in a session, and decide to delete number 7, then > sometimes you cannot get the session to save properly with a missing > number. > > In theory, if one could get the session to save, then a matrix for the > first 6 objects would still work? > > > cheers C Akey

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New chimera development snapshot available
by Greg Couch 26 Feb '07

26 Feb '07

See <http://www.cgl.ucsf.edu/chimera/docs/relnotes/snapshot.html> for details (this will be accurate for the next few days, after that read the release notes that are bundled into the chimera snapshot). The snapshot uses NumPy instead of Numeric python, so some third-party extensions may break (eg., parts of EMAN). Other highlights include intial support for PDB 3.0 (remediated PDB) format and built-in POV-Ray raytraced image support. Enjoy, Greg Couch UCSF Computer Graphics Lab

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Saving model positions
by Thomas Goddard 26 Feb '07

26 Feb '07

Hi Christopher, The problem you have with the Chimera matrixget and matrixset commands is that the matrix file lists the model number (0.0, 1.0, 2.0, ...) with each matrix. For example, Model 0.0 -0.0635922 -0.740419 0.66913 247.807 -0.979146 -0.0833402 -0.185275 540.192 0.192946 -0.666958 -0.719679 472.752 Model 1.0 0.233245 -0.923975 -0.303095 418.621 0.970522 0.201738 0.131868 -125.304 -0.0606967 -0.324918 0.943792 100.98 When you open maps and PDB files in a different order they get different numbers. Chimera assigns the lowest available number (starting at 0) each time you open a data set. Then when you use matrixset <filename> to get your standard orientation it applies the matrices to the wrong models because of the different numbering. The easiest remedy for this is to open your data sets in a fixed order (first large ribosomal map (#0), then small ribosomal map (#1), ...). This can be inconvenient. If you save a single positioning matrix in a file there is no current command to say to apply that matrix to a model that you specify as a command argument (e.g. no command like "matrixset <matrix-file> <model-number>" exists). There are some other approaches to the problem of getting standard orientations. One method is to save your ribosome large and small subunit map positions in a Chimera session. Then if you want to use different maps, open the reference session, then open the new maps and use the "matrixcopy" command http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/matrixcopy.html to position the new maps to match the reference map positions. Instead of using matrixcopy you could use the equivalent Model Panel dialog "Transform As" button to apply the positioning matrix of one map to a second map. Another command that may be helpful is "savepos <name>". http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/savepos.html It remembers the positions of all currently opened data sets and gives a name to that set of positions. You can later restore those positions with the command "reset <name>". These named positions are saved in Chimera session files. The trouble is that there is not an immediate way to apply those positioning matrices to different maps or PDB models. But that could be achieved with the matrixcopy command or Model Panel / Transform As button. If this set of capabilities does not let you easily do what you want could you describe an exact scenario (how many maps, how many models, how are they related) and if possible propose a new command that would help you. I think it would be great if density map file formats supported saving multiple named positioning matrices in their header. For example, you might want to save how a piece of a map is positioned in the full source map, and also how a piece of a map fits into different map (e.g. at various locations in a tomogram), and your case of just a standard orientation ("front view", "top view"). I do not believe any of the commonly used density map formats allow this although it may be possible to put that info into header comment fields in some map files. Tom Christopher Akey wrote: > Tom - > > ... > > Chimera is very good, but there are still problems. A new workstation > will help and will be here in a few weeks. > > However, one thing is really annoying. It is important to set a > particular view for your structure, for example a side-by-side frontal > view of the ribosome with regards to the small and large subunits. > > Once you have this in one session it would be useful to be able to > recreate this easily in other sessions. (For logistical reasons, it is > ofter easier to keep a session for each Figure so that they don't get to > crowded.) > > Right now, if you save a matrix (matrixget) and then make a change in > the session, ie delete or add a file, you get unpredictable results, but > usually, the matrix no longer works or it only works for one volume in > the session. This is not good when you have separate vols for the small > and large subunits in proper registration, you get a matrix for the > front view, and then at a later time, only one subunit will be realigned > properly! > > It would be great if you could set a matrix for a particular map as a > benchmark, then when you read that map into any other session, you could > recreate this orientation using the matrix. I don't understand why this > won't work. > > The feature of being able to bring in other maps and align them in > CHimera is great and works very well (its in our older test version that > we are using, and its very useful as we often have 3 or more structures > of the same basic object with minor diffs). > > I hope this makes sense. > > cheers C Akey >

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many days after...another question Re: Select atom by serial number.
by Jean Didier Pie Marechal 26 Feb '07

26 Feb '07

Hi everybody, I'd like to select a series of atoms by their serial number (again!!!) (e.g. from atom number 1 to atom number 10). the sel @/serialNumber=1-10 doesn't seem to be the right syntax. Is it possible to do this kind of selection? If yes, what is the right syntax please. 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: +34.935814936 e-mail: JeanDidier.Marechal(a)uab.es ----- Missatge original ----- De: Elaine Meng <meng(a)cgl.ucsf.edu> Data: Dijous, Gener 11, 2007 8:59 pm Assumpte: Re: [Chimera-users] Select atom by serial number. > > Hi JD, > We also tested Chimera 1.2309 on Windows, and these specifications > > work correctly. Example: > Command: sel @/serialNumber=232 > will select NZ of Lys 27 in chain A of the PDB entry 1zik. The > only > other thing I can think of (besides what was in the previous > message) > is to check if your PDB file is correctly formatted. The > ATOM/HETATM > serial number is supposed to be in columns 7-11 and right-justified. > Best, > Elaine > > On Jan 11, 2007, at 11:39 AM, Elaine Meng wrote: > > > Hi JD, > > You are using the correct specifications - both of your examples > > > should work. I tested both approaches in Chimera 1.2304 on Mac > OSX > > and they worked correctly. We'll have to look into your > specific > > version/platform and get back to you. If you want, you could > send > > me the PDB file you are using so I could test if there is some > > issue specific to that structure. To be clear: the serial > number > > is the number shown in the column after ATOM (or HETATM) in the > PDB > > file, regardless of what order the atoms are really in. That > is, > > if the first ATOM has 2 in that column, its serial number is 2 > and > > not 1. > > Best, > > 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 > > > > > > > > > > On Jan 11, 2007, at 10:47 AM, Jean-Didier Maréchal wrote: > > > >> Hi Everyone, > >> > >> > >> > >> > >> > >> I am desperately trying to select an atom of my pdb by its > serial > >> number. > >> > >> Looking at the archives, it seems that I should put something > like > >> @/serialNumber=525 > >> > >> I tried “sel #0@/serialNumber=525” in the commandl ine and “@/ > >> serialNumber=525” in the Atom Specifier. None of these > selections > >> worked. Can someone tell me the right way to do this, please ? > >> > >> > >> > >> Cheers > >> > >> JD > >> > >> > >> > >> Current running chimera: version 1 build 2309 > >> > >> OS: windows > >> > >> > >> > >> _______________________________________________ > >> Chimera-users mailing list > >> Chimera-users(a)cgl.ucsf.edu > >> http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users > > > >

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