Getting Started with guild

Here is a step-by-step tour of guild's main functions:
  1. Type guild to bring up the main window. If this is the first time you have used guild, you will get a welcome message in a second window, which you can read and close.
  2. Click and hold on "LDAS metadata database..." to pop up the menu of database queries, then select "List all database tables".
  3. You will be prompted for your LDAS username and password (NOT your Unix username and password!)
  4. A window will pop up to show you the status of the query job, and then after about 10 seconds, it should display a table.
  5. Double-click on the "TABSCHEMA" column heading to hide that column.
  6. Single-click on the row number to the left of the "GDS_TRIGGER" row. The row will turn yellow, and the "Cross-ref" buttons at the bottom of the window will become active.
  7. Click on "Describe table", which pops up a window to show that status of the query. After a bit, you will get a table which lists all the columns in the GDS_TRIGGER table, i.e. all the fields which may be filled in when making an entry in that table. When you are finished with this window, close it.
  8. Close the window with the list of database tables.
  9. Click and hold on "LDAS metadata database..." to pop up the menu of database queries, then select "GDS triggers". This will open a new window entitled "Build query for table GDS_trigger".
  10. Go ahead and just click on "Refresh & Submit". This will submit a query which matches all records in this table, but only the first 100 will be returned. (This limit can be changed near the top of the window, but note that queries asking for more than a few thousand records become unreasonably slow.)
  11. The GDS_TRIGGER table has a lot of columns, so you will have to scroll and/or hide columns to see the ones you want. Click on the "Help" button to find out what else you can do with a table display.
  12. Go back to the "Build query" window and click on the "List" button to the right of "trigger name". This sends a query to get a list of all trigger names which appear at least once in the table.
  13. In the list window, double-click on "Earthquake"; this pastes this trigger name back into the "Build query" window and modifies the query text accordingly.
  14. Click on "Refresh & Submit" to get a table of earthquake triggers. Note that there are really only two interesting columns in this table, for these particular triggers: START_TIME and SIZE.
  15. Back in the "Build query" window, near the top, click in the entry box to the right of "Selected:" and type in "start_time, size". Now click on "Refresh & Submit" to bring up a table containing only these two columns.
  16. Click on "Save as...", and in the window that pops up, just click on "Continue to filename selection". After saving the file, view it to see what a "LIGO lightweight" XML really looks like.
  17. Click again on "Save as...", but this time select "Save displayed data as text" with whatever formatting options you prefer.

  18. Close all of the windows except the main guild window.
  19. Note which LDAS server is currently listed in the main guild window (by default, this is set to "LHO" when you start up guild).
  20. Click and hold on "Frame data..." to pop up a menu, then select "Get raw data from sites".
  21. Click on the "Check" button to see the time range, in GPS seconds, of the data which is available (normally the last ~24 hours).
  22. Choose a time somewhere in the middle of this range and enter it as the "Start Time".
  23. Click on "Refresh & Submit". This will download the full one-second frame file (a few megabytes) into the directory you started guild from. If you are not at one of the sites, note that it takes a fairly long time to transfer this much data over the T1 line!
  24. Back in the "Build Raw Data Request" window, click on the "List" button to the right of the "Channels" entry box. This will submit a query to return the current channel list.
  25. Double-click on a few of the channels in the list, which causes them to be inserted into the "Build Raw Data Request" window.
  26. Click on "Refresh & Submit", and note that this request returns a much smaller frame file.

  27. Close all of the windows except the main guild window.
  28. Click and hold on "Utilities..." to pop up a menu, then select "Time converter" to bring up the Time Converter window. Initially, the input field is set to "now", so that the current time (according to your computer) is displayed.
  29. Replace "now" with a date/time string, such as "jan 28, 2001 5:44". Experiment with this for a while; it handles pretty much any unambiguous date/time string. Also, you can enter things like "now - 1 day".
  30. Enter a GPS time, such as "650000000", to see that it gets converted to a date/time string. Also, enter "1000000000" to see that GPS times will become 10-digit numbers within LIGO's lifetime. Prepare early for the "GPS Billion Bug" !

Problems? Questions? Contact Peter Shawhan <shawhan_p@ligo.caltech.edu>