CmsShow is invoked as follows:
./cmsShow.exe [options] <data file>
For most uses, no options are required.
Allowed options:
-i [ --input-file ] arg Input root file
-c [ --config-file ] arg Include configuration file
-g [ --geom-file ] arg Include geometry file
-n [ --noconfig ] Don't load any configuration file
-p [ --play ] arg Start in auto playback mode with given interval
between events in seconds
--port arg Listen to port for new data files to open
--eve Show Eve browser to help debug problems
-r [ --root-interactive ] Enable root prompt.
-d [ --debug ] Start the display from a debugger and producer a
crash report
-s [ --shine ] Use advance options to improve rendering quality
(anti-alias etc)
--soft Try to force software rendering to avoid problems
with bad hardware drivers
-h [ --help ] Display help message
In the default configuration, CmsShow knows about the following objects:
Not all these objects are visible by default; see Visible and invisible items below. Each type of object has a color, which can be used to distinguish it from other objects. The color is the same across views; for example, the default jet color is yellow, and jets show up in yellow in all views. See Controlling object properties to learn how to manipulate the object properties (visibility and color).
Multiple views of the event are available.
To keep track of objects, two handy features are available. Hovering over an object with the mouse in any view makes the object light up in all other views (as well as displaying a small information window about the object). Clicking on an object selects it (see Selecting below) in all views.
The view area is divided into one "big" area and multiple "small" areas; the icon in the top left corner of each view swaps that view into the big area. The graphical views and tables can be "undocked" from the main CmsShow window by clicking the "undock" icon. This is handy if you want to see the graphical views of the event and the detailed information in the tables side-by-side, for example, or if you want to show several views in large windows.
Some views have additional properties. These can be changed with the View Controller, which is brought up by clicking on the view title bar.
Views can be removed (with the icon in the top right corner of the view) or added (through the File -> New Viewer menu).
For some objects, more detail is available through detailed views. These detailed views can be opened by selecting an object (by clicking on it), then pushing the "Open Detailed View" button in the Object Display Controller (for more information about the Object Display Controller, see Controlling object properties).
Each object has two properties: color and visibility. The user can select a non-default color for an object, for example to identify a "special" electron in all views. The visibility flag is used primarily to keep low-energy objects from cluttering the views. Both properties are controlled by the Object Display Controller. This controller window opens the first time an object is selected (by clicking on an object); if it is subsequently closed, it can be re-opened from the Window -> Show Object Display Controller menu.
Collections have the same properties as individual objects: color and visibility. The collection properties can be controlled from the Collection Controller. To open this window, click a collection name in the list view or use the Window -> Show Collection Controller menu. The collection visibility flag is used to keep the views uncluttered by hiding some collections.
The Collection Controller can also filter and select items in a collection. (For example, it can make all jets with Et < 15 GeV invisible.) See Filtering and Selecting below.
To limit clutter in the views, it may be desirable to make low-energy objects invisible. "Filtering" is accomplished by entering a filter expression in the Collection Controller window (see Controlling collection properties above). This expression is interpreted using CINT. (For convenience, the special symbol $ can be used as shorthand for the collection name.) The objects for which the filter expression is false become invisible in the graphical views; they are shaded in the text tables and moved to the end of the table.
Selection is a useful tool for keeping track of objects in the different views. An object can be selected by clicking on the object in any view. The selection propagates to all other views. Multiple objects can be selected by holding the Control key while clicking (this toggles selection). For example, if a muon sparks the user's interest in the rho-phi view, the user can find out more about the muon by selecting it and reading the selected row in the muon table. (It may be more convenient to have the rho-phi view and table in separate windows so they can be viewed side-by-side. To do this, the table can be "undocked" from the CmsShow window with the "undock" button; see Views above.)
Objects can also be selected using the "Select" tab of the Collection Controller (see Controlling collection properties above). The selection is performed by entering an expression. See the description for the filter expression in Filtering above.
Collections can be removed from the event display by pushing the "Remove Collection" button in the "Data" tab of the Collection Controller (see Controlling collection properties).
Additional collections can be added to the event display with the Add Collection feature. This window is opened by clicking the + button above the list view or with the Window -> Show Add Collection menu. The user can pick a collection from a list of all collections present in the data file. (To sort the list of collections, click on the column headers.) A useful example application is to add jets that were clustered with a different algorithm than the default jets (iterativeCone5CaloJets), set their color to green, and compare the yellow and green jets in the lego view.
The configuration of the event display (collection colors etc.) can be saved with the File -> Save Configuration menu. Likewise, a saved configuration can be loaded with the File -> Load Configuration menu.
To save a copy of a graphical view, use the File -> Export Main Image menu or the Save Image button in the View Controller. The tables can be dumped to the terminal or into a text file, or they can be piped to a print command (lpr or something fancier like enscript), using the buttons at the top of the table.
To open a data file, use the File -> Open Data File menu.
You can navigate between events with the arrow buttons above the list view or by entering a run and event number in the fields to the right of the navigation buttons.
To show only events that pass a filter, enter an expression in the "Filter" field to the right of the navigation buttons. This expression is interpreted by CINT, and only events for which the expression is true are displayed. For convenience, collections can be referred to by their CmsShow names (the names displayed in the list view) rather than their fwlite names. Thus, "$Electrons.pt() > 10" would select events where there is at least one electron in the Electrons collection ("pixelMatchGsfElectrons" by default) with 10 GeV pt.