February 2020 - ChimeraX-users - RBVI Mailing Lists

Re: [chimerax-users] [Chimera-users] color by zone in chimeraX
by Elaine Meng 20 Nov '20

20 Nov '20

Hi Pranav, I’m Cc'ing the chimerax-users(a)cgl.ucsf.edu list (recommended for ChimeraX questions). I believe the problem is that when coloring the chains you are using “target c” which means to color only cartoons, whereas coloring by zone uses the atom colors. Since you only colored the cartoons, the atoms probably still had heteroatom color-coding. If you use “target ac” instead (even if the atoms aren’t shown), then as long as the color zone distance is big enough, I think you will get the color zones you expect. <http://rbvi.ucsf.edu/chimerax/docs/user/commands/color.html#simple> <http://rbvi.ucsf.edu/chimerax/docs/user/commands/color.html#zone> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Aug 20, 2019, at 10:54 AM, Pranav Shah <p.shah.lab(a)gmail.com> wrote: > > Hi Elaine and Co., > > I am trying to color a virus map with the relevant pdb file, the > series of commands I am running are as follows, > open virus.mrc > open virus.pdb > color /A plum target c > color /B lightgreen target c > color /C dodger blue target c > color zone #1 near #2 dist 3 > However, the resultant surface is rendered in splotches of red and > blue, which leads me to think the it is coloring the surface using > atom type. Could you tell me how I can get Chimera X to color the > surface using the colors of the chains only? FYI, color by zone works > flawlessly in chimera. > > Cheers, > Pranav

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Map "Blobs" tool - Generate objects?
by Christophe Leterrier 11 May '20

11 May '20

Hi, I started using ChimeraX for visualization and quantification of 3D microscopy images. The "blob" tool is particularly impressive to semi-automatically segment objects of interest and measure their characteristics. However, I could not find a way to generate an independent object from the picked blobs. This makes the quantification process unreproducible as it is not possible to store the blobs in the session or automatically measure all the picked blobs. Am I wrong in the intent of the tool, or is there a way to do this? Thank you, -- Christophe Leterrier NeuroCyto lab INP CNRS UMR 7051 Aix Marseille University, France

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bundle_info.xml API changes
by Eric Pettersen 01 Apr '20

01 Apr '20

Any non-developers feel free to skip this message. Even for developers, unless you are writing a toolshed bundle that uses the DataFormat, Open, Save, and/or Fetch tags in the bundle’s bundle_info.xml file, you could skip this message. For the two of you that are left, in anticipation of the the ChimeraX 1.0 release sometime this year we are changing some APIs we are unhappy with. Namely, the tags in the in bundle_info.xml that I mentioned in the previous paragraph. As they stand, they are not easily extensible and it is not obvious without looking at the documentation what the various fields do. On top of that, it is difficult to take the information in those tags and present interfaces for options in ChimeraX’s Open/Save file dialogs. Also, there is nothing preventing keywords added to the open command by one bundle from conflicting with keywords added by another bundle. We will be migrating those tags to use bundle_info’s Manager/Provider architecture (described here <https://www.cgl.ucsf.edu/chimerax/docs/devel/tutorials/bundle_info.html>). Instead of fixed fields, you have keyword/value pairs, which is slightly more self-documenting. Also, a manager can ask a provider for various things, so in one case the manager can provide a partially processed “open” command along with the “rest of line” for the provider to handle its options, if any, and actually open the file, whereas in another the manager can ask for a widget containing options to show in an open or save dialog. In brief, the change allows us to solve some issues that looked pretty intractable with the old scheme. The exact details of the managers and providers supporting these functions are not detailed in that link (just the generic mechanism), but details will be added as implementations are completed. For convenience, there will some period of time when both the old scheme and new scheme will both work, but we anticipate dropping the old scheme before the 1.0 release. —Eric Eric Pettersen UCSF Computer Graphics Lab

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volume onesmask usage question
by Alexis Rohou 30 Mar '20

30 Mar '20

Hi there, I was trying to use "volume onesmask" to go quickly from a dusted surface of a low-pass-filtered volume to a mask volume with the same dimensions, spacing, etc. as the input map. I thought "fullmap" might be a way to achieve this (the doc says "The remaining options are the same as described for volume mask"), but I don't think that option actually works with "volume onesmask": volume onesmask #3 fullmap true *Expected a keyword* Is there a "onesmask"-like operation or set of options that creates an output volume that's on the same grid as the input volume? Thanks, Alexis

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Secondary structure display - pdb and cif
by Tetter Stephan 04 Mar '20

04 Mar '20

Dear ChimeraX users and developers, I am having an issue with secondary structure display. I am real-space refining a set of 120 chains in phenix. Of these, only 10 are unique, the rest is symmetry-related. Thus, I define secondary structure elements for the 10 unique chains only. The output pdb file header contains the secondary structure elements as imposed during refinement. Displaying this pdb file in ChimeraX shows the right secondary structure. The mmcif file instead, whether I use the phenix output or generate it from the pdb myself, displays different, non-sensical structures. Secondary structure is shown in loop regions, and some actual strands and helices not recognized at all. This artifact is only shown for the 10 subunits with secondary structure definitions, the other subunits show no secondary structure at all, thus something is read in, but not correctly, apparently. Any idea what the problem could be? Could the size of the complex be an issue? The attachments show the lines from the two file types concerning secondary structure definitions. Kind regards, Stephan

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Bug: selection of atoms by attribute = color
by Pavol Bardy 393791 27 Feb '20

27 Feb '20

Hello, since version 0.91 I am experiencing problems with selecting atoms by color attribute "@@color=color". I am getting an error message "Expected an objects specifier or a keyword". In version 0.90 everything works fine. Other attributes like "bfactor" or "idatm_type" seems to work normally. Kind regards, -- Pavol Bárdy Laboratory of Microbial Molecular Diagnostics Department of Experimental Biology, Masaryk University Kamenice 5 / A25 Brno, 625 00, Czech Republic

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change residues to helix
by Meinan Lyu 24 Feb '20

24 Feb '20

Dear cgl.ucsf.edu, In chimerax, Helix is disrupted for some reason, could I change the intermediate residues into helix? There are two ways I tried, 1: use 'dssp' command, 2: use 'setattr :467-469/A res ss_type 1'. But both didn't not work. Could you tell me how to change this? Best regards, Meinan [image: image.png]

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Default mrc/ccp4 file opening by ChimeraX
by Kim, Doo Nam 20 Feb '20

20 Feb '20

I use mac (10.14.6). But when I double-click mrc/ccp4 file, chimera automatically opens it. I want to open it with ChimeraX (which is faster). However, even when I right-click on ccp4 file -> open with -> always open with -> ChimeraX_Daily, only that specific file is opened with chimera automatically. Does anyone know how to set up so that all (including future) .mrc and .ccp4 files are opened with ChimeraX? Thank you Best, Doonam

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Error in reopening session
by Maximiliane Wieland 20 Feb '20

20 Feb '20

Hi, When I try reopening a session I have been using for two weeks now (so many saved view :( )and I get the following error: Unable to restore session, resetting. Traceback (most recent call last): File "/Applications/ChimeraX_Daily.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/chimerax/core/session.py", line 653, in restore obj = sm.restore_snapshot(self, data) File "/Applications/ChimeraX_Daily.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/chimerax/basic_actions/statemgr.py", line 65, in restore_snapshot cmd.name_frozen(session, name, Objects(**value)) File "/Applications/ChimeraX_Daily.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/chimerax/basic_actions/cmd.py", line 54, in name_frozen raise UserError("nothing is selected by specifier") chimerax.core.errors.UserError: nothing is selected by specifier This is the error from the daily build, in the production release one I get the same error, only difference is in "cmd.py", line 52, in name_frozen When trying to open an older version (that I saved but did not open, since I kept using the same session and saved it to the latest version) I am asked to replace missing files, which are in fact not missing but still in the very same directory and with the very same name, so it feels like the real error lies elsewhere? Can I make it reopen the session without reopening the volume? The last version of the session I can open without a problem is close to two weeks old, I named some selections in the meantime, could that cause such an error? I use ChimeraX on MacOS X 10.12.6 I will also submit the bug but since it is kind of urgent I thought I would try submitting here, too, in hopes of a quick response. Best, Maxi

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Set view
by Aritz Roa Eguiara 19 Feb '20

19 Feb '20

Dear ChimeraX, I am trying to produce a script .cxc to open on ChimeraX and I want to set a specific camera position coordinates that can be opened by anyone. I do obtain the position by just using the command camera, but then I do not know how to obtain that position without saving the view. How should this be written on the command line so that anyone can open it and get that view? For example, I know that PyMol allows the get view command to obtain all the information that later only need to be pasted on the script, is there anything similar? Thank you in advance for your help. Best regards, Aritz

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ChimeraX-users February 2020