emu.track {emu} | R Documentation |
Takes the result of a database query and retrieves corresponding time-series data from the database.
emu.track(seglist, trackname, cut=NULL, npoints=NULL, template=attr(seglist, "database"))
seglist |
An Emu segment list. |
trackname |
The name of the data track to retrieve, a string. This must be a track name defined in the database template. |
cut |
An optional cut time for segment data, ranges between 0 and 1, a value of 0.5 will extract data only at the segment midpoint. |
npoints |
An optional number of points to retrieve for each segment or event. For segments this requires a cut= argument and data is extracted around the cut time. For events data is extracted around the event time. |
template |
The database to retrieve the data from, this should not normally be set. |
emu.track
takes a segment list as input
and retrieves associated numerical data from the corresponding
database. The segment list will usually be the result of a call
to emu.query
but could be constructed with the
make.seglist
function. The result is either a
two dimensional array of data or an object of class
trackdata
which may contain multi-column data
from many tokens.
If only two arguments are supplied the entire data track is
retrieved for each segment in the segment list. The amount of data
returned will depend on the sample rate and number of columns in
the track requested. The returned data is packaged up as a
trackdata object.
The optional cut
argument specifies a cut
point as a fraction of the duration of each segment in the segment
list. If this is specified the data at this single cutpoint will
be extracted rather than that for the entire track. The result of
emu.track
with the cut arguement is a two
dimensional array of data with one row per segment in the original
segment list and one column per column in the requested
track. This array can be treated like any other array in Splus.
If the input segment list is in fact an event list (ie. is
derived from an annotation level defined as events in the database
template) then the result of emu.track
is the
same as if the cut argument was specified.
If the npoints
argument is specified, it defines the number of
points that will be returned for each segment or event. The
cut
argument is required if the input is a segment list (as
opposed to an event list).
This function calls external scripts via tcltk which are part of the Emu speech database system and so requires this system to be installed on your computer. See the Emu web site for details.
Steve Cassidy <Steve.Cassidy@mq.edu.au>
See the Emu documentation at: http://www.shlrc.mq.edu.au/emu
## assumes a database called demo is available on your system and that ## the Emu system is installed. data(vowlax) # find all Phonetic vowels in the database ## Not run: segs <- emu.query("demo", "*", "Phonetic=vowel") # get formant data at the midpoint, returns an array ## Not run: data.mid <- emu.track( segs, "fm", cut=0.5 ) # get formant data for entire tracks, returns trackdata ## Not run: data.all <- emu.track( segs, "fm" ) summary(data.all)