LIGOtools -- Frequently Asked Questions

Please help your fellow collaborators! To contribute to this page (with a text file, a link to somewhere else, etc.), contact shawhan_p@ligo.caltech.edu. To report an inaccuracy, submit a correction, etc., contact the author of the relevant section and/or shawhan_p@ligo.caltech.edu.

General

• How do I install LIGOtools?
• What do I need to do to use LIGOtools? (assuming it's already installed)
• How can I find out what LIGOtools packages (and versions) are installed?
• What should I do if the precompiled binary version of a LIGOTOOLS package does not work on my system?
• How can I remove (uninstall or deactivate) one or all versions of a LIGOtools package?
• Matlab can't find frextract (or some other LIGOtools M-file or MEX-file). What's wrong?

LDAS database / LIGO_LW files
(These items apply to all LIGO_LW files containing Table objects, whether or not they were extracted from the LDAS database.)

• How can I retrieve data from the LDAS database?
• How can I read a LIGO_LW file of table entries into ROOT (using the Event Analysis Tool)?
• How can I read a LIGO_LW file of table entries into Matlab?
• How can I read a LIGO_LW file of table entries into a C program?
• How can I select certain entries from a LIGO_LW table file?
• What else can I do with a LIGO_LW file of table entries?
• How can I work with a large amount of data from the LDAS database?
• How can I create a LIGO_LW file containing a table of my own construction?

Frame data

• How can I look at frame data in the LIGO data archive using Diagnostic Test Tools?
• How can I get LIGO frame data onto my local disk?
• How can I look at frame data on disk using Diagnostic Test Tools?
• How can I look at remote frame data that is served out using the LARS protocol?
• How can I merge frame data from the two LIGO sites?
• Can I get a tape of LIGO data?
• How can I read frame data into Matlab?
• How can I read frame data into ROOT?
• How can I get a list of the channels in a frame file?
• How can I get an ASCII dump of the contents of a frame file?
• How can I look at trend data?
• How can I create a frame file with simulated data?

Data monitoring

• How can I look at real-time LIGO data from outside of the control room?
• How can I use the DMT Viewer from outside of the control room?
• How can I look at trend data?

LDAS

• How can I get an LDAS username/password?
• How do I store my LDAS username/password so that LIGOtools utilities can use them?
• How can I submit an LDAS user command?
• What should I do if there is a problem with LDAS?

Miscellaneous topics

• How can I use LIGOtools programs from behind a firewall?
• How do I use LIGOtools packages which are based on ROOT?
• How can I convert between GPS time and UTC or local time?
• What are other sources of LIGO data?