roottree

DESCRIPTION

This command allows SpecTcl to write root trees from the unpacked parameters. Root Tree writers act as a Event sink, but are linked to an event processor so that they are aware when run start/stop records are encountered.

The create subcommand creates a new tree named tree-name the parameters that match any of the list of glob patterns in parameter-pattern-list will be written to the tree. If gate is supplied, branches will only be written to the tree for events that satisfy that gate name.

The delete subcommand deletes the root tree named by tree-name. Deleting the tree does not remove it from any open Root file. All it does is prevent that tree from having any further branches written in any open root file and from existing in any future root file.

The list subcommand produces a Tcl list of trees that are currently defined. If the glob-pattern tree-name-pattern is supplied, only those trees whose names match that pattern will be listed. If tree-name-pattern is omitted, the default glob pattern, *, matches all trees.

The output of the list subcommand is a Tcl list of tree descriptions. Each description consists of a three element sublist. The elements of that sublist are, in order, The tree name, the list of parameter patterns defining the written parameters and the name of the gate that conditionalizes branch creation in the tree. If no gate was selected, this will be the string -T- indicating a True gate is used.

The name of the root file written is run-runnumber.root in the current working directory of the login. If it's necessary to write trees but no begin run item has been seen, the trees will be written to the file SpecTcl-seq.root where seq is the number of times we've been asked to start writing tree data without seeing a start.

Typically the case of not seeing a start occurs when attachingh to an online data source.