Open Files - D0DAD Catalog Access - Output File

You should see the following picture when you push this button:

Note that each item in the menu list, where appropriate, has a ^z symbol associated with it (where "z" is P for Open Data File... and etc). This means you can access the item via control-z (e.g. control-P for Open).

Open Data File... ^P

This is how you get access to files (data, STP, or D0DADF) (keep reading!). Pushing this button will cause a "File Selection Box" to appear. It will look like this:

In the text area under the word "Filter" you see the string "top5$hroot:[e_jets.data]*.*". This particular string will be your current default directory. The program takes this "filter" and applies it (via "dir" or "ls") with the result displayed in the text under the word "Files". To the left of this is a list of directories, with the current directory, the one above, and all below. The following functionality is at your disposal:

• Directory Navigation. By double-clicking in the appropriate directory name, you can "go there".
• File Filtering. To change the "Filter" just use the mouse, highlighting and deleting as usual. Then hit the Filter button (lower button, second from the left) and the filter will be applied. For instance, if you only want to see files which satisfy top5$hroot:[e_jets.data]all*20*.x_udst you can change the "Filter" to this string, hit the "Filter" button, and only those files which satisfy the filter will appear in the "Files" text window.
• File Selection. To select a file, you can either double-click on one of the selections in the "Files" list, or you can click once on the selection and hit the "OK" button (bottom left button). Note that for the latter method, you'll see the selection appear in the "Selection" text window (the one just above the bottom row of buttons). An alternate way of opening a file is to just type it into the "Selection" window by hand and hit the "OK" button.
• Using Wild-cards (*). You can open files via wild-cards in D0X by typing the desired wild-card string in the "Selection" window and hit "OK". For instance, if you want to open all of the micro-dsts listed above, you can type top5$hroot:[e_jets.data]all*.x_udst in the "Selection" window and hit "OK". D0X will find the first file which satisfies the condition and open it. Subsequent files will be open if you are doing a loop over events (see D0X Control).

Note also that you do NOT need to close files - this will be done for you automatically (by D0OPEN).

D0DAD Catalog.... ^B

D0DAD stands for D0 Direct Access Data. John Hobbs is responsible for bringing the system from OPAL. What D0DAD does is to organize pointers to the data within files (D0DADF files) or to put event information into "catalogs" which themselves contain information about where events are located. Push this button (D0DAD Catalog...) if you want to access particular events via the catalogs (D0DADF files are accessed just like regular data files, see above), and the following window should appear:

The first thing to notice are the two buttons labelled Standard Catalog and Specify Catalog. The D0 RECO program will be putting data into standard catalogs hot off the press. The name of the catalog will be run-dependent, the program will know which catalog to open. Note that this will work transparently to any user on one of the FNAL machines, but if you are off site you will have to have the correct VMS logicals (or have the D0FS system file mounted if you are on unix) set up (it's d0$d0dad$catalogs:run*_mds.evtcat). The Standard Catalog button is set to tell you that the program will go to the standard D0 catalogs. However, if you want to open some other catalog, hit the Specify Catalog button. You'll get another File Selection window which will look like this on VMS:

Note that the "Filter" is set to point to the standard D0 catalog area.

Specifying the catalog of choice only tells the program which catalog to open. Nothing happens until you specify the Run and Event numbers by typing them into the appropriate boxes and hitting the button labeled Fetch Event. The program then goes to the catalog which you've specified, opens it, gets the information as to where the event lives, and goes and gets the event.

Output.... ^O

You can use D0X to write events into an output file. The control menu for output is accessed by clicking this button, and will look like this:

• How to Open Files

  To open a file, you must do the following:

  1. Type the file name in the bottom text area (below the words Enter filename below:
  2. Hit <cr> or push the Open button.
  You should see some FZOPEN information typed onto your screen.

• Closing Files

  The only way to do this is to push the Close button. Look on your terminal window when you do this for the FZENDI information about how many bytes were written, etc.

• Native or Exchange Mode

  Self explanatory!

• Writing the current event

  Push the button labelled Write This Event. The event will be written to the file. If all goes well, the counter will be incremented (see below).

• Automatic Output

  Pushing this button will cause the following options to be displayed:

  

  The options are described here:

  • DISABLED

    This is the default, and cancels any of the above so that you only output events when pushing the Write This Event button (see above).

  • All Events

    This option will cause every record which is read from the input to be copied to the output. Note that you can use D0X to combine events from several files into a single file (e.g. some of the streaming results in files with just a few (event 1!) event - you may want to combine them using this feature). Note that to make D0X cycle through all records (events) in a file you will have to go to the Control menu and hit the All button (see reading in all events).

  • From Query

    You can set up a simple query on the data (see queries). The result of the query is either true (satisfied) or false (not satisfied). You can use the query to control wether to save the event into the output file by selecting this option. For instance, if you want to strip off all events which have 2 electrons each with ET>20 GeV, you set up the query, open the output file, set auto to From Query, and hit All from the control menu.

  • From List...

    If you have a list of run and record numbers of events in a particular file which you want to strip off, you can do it by:

    1. Open a file for output (see above)
    2. Make an ascii file of the numbers, one event per line, like this:

             57066 2352›1
             64002    336
       

    3. Select this option (From List...). The program will prompt you for the file name which contains the list. It will read in the list and tell you how many items there were (to be sure everything went ok).
    4. Hit the all button in the Control menu and watch the counters increment.
    Note that the program will not stop when the entire list is exhausted, but will blindly go to the end-of-file looking for events which are included in the list. You can stop when you know the list has been served (by looking at the output counter) by hitting the halt button in the Control menu.

  • From D0XUSER

    After each event is read in, the logical function D0XUSER is called. The result of D0XUSER is either true or false. You can use this result to control whether or not to write the event to the output file (see d0xuser).

• Event Counter

  This counter will tell you how many events were actually written to disk. Reset the counter by pushing the Reset button.

Attributes:

There is a series of buttons here which again you will almost never have to play with, but are described now.

• Destination: ZEBCOM

  This is an "Option Menu" which allows you to change the zebra common. The default is ZEBCOM, but if you are opening an STP (see STP Files)) file you will have to change it to ZEBSTP, and etc. for a GEANT file, or if you want to use ZEBWRK. From experience, the only thing which you will probably want to do is to change it to ZEBSTP to open STP files.

• Mode: EXCHANGE

  Since D0OPEN will determine whether the file is in EXCHANGE or NATIVE mode before it opens it, this attribute is obsolete.

• File type: FZ

  The default file type is FZ for data file. If you want to open an STP file, change this to STP. Note that if you are opening D0DADF files, the code opens the catalog in the appropriate way and sends you the event, so you don't have to change this attribute.