Hi, I want to handle a large number of small density maps (around 1000 maps of approx 50x50x50 pixels). I need to group them (in around 5 groups). Then I need to treat all the maps of each group in a certain way. For example, I would like to change the level threshold for display, or the display style for every maps in a group at once. Also I would like to show or hide all maps of a group at once. The maps are not opened in an order related to their group. I remember someone recently suggested model 'folders' as a new functionality. Has this been incorporated in the latest versions of chimera? Even if it is the case, It would be too tedious to have to click on each individual model to assign it to a group. Similarly a simple command passed at the command line wouldn't be very elegant: I would have to write each volume number since they are unsorted. I suppose a python script would be much more appropriate. The script would have some functions to do tasks like those described above on each members of a group and a function to read group composition from a text file. I looked in chimera's programmer guide for a section on volume handling but I couldn't find much material on that. Did I miss it? What approach would you recommend? I guess I could use runCommand() but there are maybe better ways. Also the script would have to run in interactive mode. I suppose that IDLE would work for that purpose. How should I do that? Open IDLE and import my module? Where can you define the paths that chimera uses to look for packages? Thanks in advance! Ben -- Benoît Zuber MRC Laboratory of Molecular Biology Hills Road Cambridge CB2 0QH United Kingdom +44 1223 402209 bzuber@mrc-lmb.cam.ac.uk