List of Frame Accessors

Inferometer data is written out as frames. Frames are composed of structures. Not all possible structures appear in a particular frame. The attributes listed here are in alphabetical order and does not implied their order in the frame.

For detailed description please refer to Frame Specification documents.

Structure: Frame Header - FrameH

Accessor Name Description Summary Accessible via ldas
 GTimeN   Frame start time residual in GPS seconds
Yes
 GTimeS   Frame start time in GPS nanoseconds
Yes
 ULeapS   Number of leapseconds between GPS/TAI and UTC
Yes
 dataQuality   32bit word to denote quality of data
Yes
 dt   Frame length in seconds
Yes
 frame   Frame number, increase monotonically for run
Yes
 run   Run number
Yes

Structure: ADC Data - FrAdcData

Accessor Name Description Summary Accessible via ldas
 bias   DC bias on cahnnel
Yes
 channelGroup   Channel grouping number
Yes
 channelNumber   Channel number
Yes
 comment   Comment
Yes
 dataValid   Data valid flag
Yes
 fShift   frequency in the original data that corresponds to 0 Hz in heterodyned serices
Yes
 nBits   Number of bits in A/D output
Yes
 phase   Phase of heterodyning signal at start
Yes
 sampleRate   Data acquisition rate
Yes
 slope   ADC calibration
Yes
 timeOffset   Offset of 1st sample relative to frame start time
No
 units   ADC calibration input units
No

Structure: Detector - FrDector

Accessor Name Description Summary Accessible via ldas
 armXaltitude   Altitude angle of X arm
Yes
 armXazimuth   Orientation of X arm
Yes
 armXmidpoint   Distance between the detector vertex and middle of X cavity
Yes
 armYaltitude   Altitude angle of Y arm
Yes
 armYazimuth   Orientation of Y arm
Yes
 armYmidpoint   Distance between the detector vertex and middle of Y cavity
Yes
 elevation   Vertex elevation
Yes
 latitude   Detector vertex latitude
Yes
 localTime   Local seasonal time (UTC)
Yes
 longitude   Detector vertex longtitude
Yes
 prefix   Channel prefix for this detector
Yes

Structure: Event - FrEvent

Accessor Name Description Summary Accessible via ldas
 GTimeN   GPS time residual of event in nanoseconds
Yes
 GTimeS   residual GPS time in seconds
Yes
 amplitude   Continuous output amplitude returned by event
Yes
 comment   Comment
Yes
 eventStatus   Defined by event search algorithm
Yes
 inputs   Input channel and filter parameters
Yes
 nParam   Number of additional event parameters
No
 parameterNames   Array of parameter names
No
 parameters   Array of additional event parameters
No
 probability   Likelihood of event if available
Yes
 statistics   Statistical description of event
Yes
 timeAfter   Signal duration after
Yes
 timeBefore   Signal duration before
Yes

Structure: History - FrHistory

Accessor Name Description Summary Accessible via ldas
 comment   Post processing program name and comments
Yes
 time   Time of post processing
Yes

Structure: Message Log Data - FrMsg

Accessor Name Description Summary Accessible via ldas
 All variables   All message log data variables
No

Structure: ProcData - FrProcData

Accessor Name Description Summary Accessible via ldas
 BW   Resolution bandwidth
Yes
 auxParam   Auxiliary parameters
No
 auxParamNames   array of auxiliary parameter names
No
 comment   Comment
Yes
 fRange   Frequency range
Yes
 fShift   Frequency in original data that corresponds to 0 Hz in heterodyned series
Yes
 nAuxParam   Number of auxiliary params
No
 phase   Phase of heterodyning signal at start of dataset
Yes
 subType   Subtype for f-Series
Yes
 tRange   Duration of sampled data
Yes
 timeOffset   Offset of 1st sample to frame start time
Yes
 type   Type of data object
Yes

Structure: Serial Data - SerData

Accessor Name Description Summary Accessible via ldas
 data   Pointer to ascii string
Yes
 sampleRate   Sample rate
Yes
 timeNSec   Time of data acquisition, residual
Yes
 timeSec   Frame start time
Yes

Structure: Simulated Data - FrSimData

Accessor Name Description Summary Accessible via ldas
 comment   Comment
Yes
 fShift   Frequency in original data that corresponds to 0 Hz in heterodyned series
Yes
 phase   Phase of heterodyning signal at start of dataset
Yes
 sampleRate   Simulated data sample rate
Yes
 timeOffset   Offset of 1st sample to frame start time
No

Structure: Simulated Event Data - FrSimEvent

Accessor Name Description Summary Accessible via ldas
 GTimeS   Maximum event time in GPS seconds
Yes
 GTimeN   GPS Time in residual nanoseconds
Yes
 amplitude   Continuous output amplitude
Yes
 comment   Descriptor of event
Yes
 inputs   Input channels and filter parameters
Yes
 nParam   Number of additional parameters
No
 parameterNames   Array of parameter names
No
 parameters   Array of additional event parameters
No
 timeAfter   Signal duration after in GPS
Yes
 timeBefore   Signal duration before in GPS
Yes

Structure: Static Data - FrStatData

Accessor Name Description Summary Accessible via ldas
 All variables   All static data variables
No

Structure: Summary - FrSummary

Accessor Name Description Summary Accessible via ldas
 All variables   All summary variables
No

You can access the frame structures and frame accessors via the ldas user command getFrameElements.

Using a test frame created on ldas-dev, you can issue various types of queries to get the information.

  1. An example of getting Serial data frame accessors:

    ldasJob   { -name   "username"   -password   "********"   -email   "user@foobar.edu"}  { getFrameElements  -returnprotocol   "http://results"   -outputformat   { ilwd ascii }   -framequery   { R_std_test_frame_ver6 T {} 600000000-600000000 Event(1) }   }

    Message from LDAS:

    
    Your results:
    results.ilwd
    can be found at:
    http://131.215.115.248/ldas_outgoing/jobs/LDAS-DEV_5495/LDAS-DEV54958901/
    
    =========================================
    'LDAS API'          'CLOCK TIME(seconds)'
    =========================================
    Wait Time(queue):                 2.06
    ligolwAPI:                        0.10
    datacondAPI:                      0.37
    frameAPI:                         5.64
    diskcacheAPI:                     0.97
    managerAPI:                       0.31
    -----------------------------------------
    managerAPI(total):                7.40
    =========================================
    
    ldas-dev running LDAS version 1.8.0
    
    The contents of result.ilwd:
    
    <?ilwd?>
    <ilwd comment='LDAS-DEV54958901 /scratch/test/frames/assorted/T-R_std_test_frame_ver6-600000000-1.gwf {getFrameSerData 0}'>
        <ilwd name='TesT::SerData:2:2:Frame' size='4';>
            <int_4u dims='2' name='time';>2 2;</int_4u;>
            <real_4 name='sampleRate'>1.0000000e+00</real_4>
            <lstring name='data' size='4';>TesT</lstring>
            <real_8 name='dt'>1.0000000000000000e+00</real_8>
        </ilwd>
    </ilwd>
    
  2. An example of getting non-existent or unsupported frame accessors in framequery:

    query for the 2nd element of Event structure which does not exist.

    ldasJob   { -name   "username"   -password   "********"   -email   "user@foobar.edu"}  { getFrameElements  -returnprotocol   "http://results"   -outputformat   { ilwd ascii }   -framequery   { R_std_test_frame_ver6 T {} 600000000-600000000 Event(1) }   }

    Message from LDAS:

    
    Subject:
    LDAS-DEV54960395 error!
    frame::runNewJob: frame::collectElements: {T-R_std_test_frame_ver6-600000000-1.gwf: frame::method2ptr: 1st try:
     'getFrameEvent(_00424068_p_FrameH 1): event_not_found' 2nd try: 'getFrameEvent(_00424068_p_FrameH): Wrong # args. :
     getFrameEvent frame eventName  argument 2' 3rd try: 'getFrameEvent(_00424068_p_FrameH 1): event_not_found' 4th try: 
     'getFrameEvent(_00424068_p_FrameH): Wrong # args. :getFrameEvent frame eventName  argument 2'}
    
    =========================================
    'LDAS API'          'CLOCK TIME(seconds)'
    =========================================
    Wait Time(queue):                 1.85
    frameAPI:                        29.93 (ERROR)
    diskcacheAPI:                     0.82
    managerAPI:                       0.29
    -----------------------------------------
    managerAPI(total):               31.04
    =========================================
    
    ldas-dev running LDAS version 1.8.0