Function to extract a vector or matrix from EMU-Trackdata at a single time point of to create another EMU-trackdata object between two times.
A general purpose tool for extracting data from track objects either at a particular time, or between two times. The times can be values in milliseconds or proportional times between zero (the onset) and one (the offset).
dcut( trackdata, left.time, right.time, single = TRUE, average = TRUE, prop = FALSE )
trackdata |
An Emu trackdata object. |
left.time |
Either: a numeric vector of the same length as there are observations in trackdata. Or: a single value between 0 and 1. In the first case, the left time boundary of trackdata[n,] is cut at left.time[n], in the second case, and if prop=T, it is cut at that proportional time. |
right.time |
Either: a numeric vector of the same length as there are observations in trackdata. Or: a single value between 0 and 1. In the first case, the right time boundary of trackdata[n,] is cut at right.time[n], in the second case, and if prop=T, it is cut at that proportional time. |
single |
If TRUE, one value is returned per segment. This applies when the requested time falls between two track frames. When single=TRUE, the preceding value is returned, unless average=TRUE (see below), in which case the average value of the two frames is returned. when the right.time argument is omitted |
average |
A single element logical vector - see single above. Applies only when the right.times argument is omitted and when single = TRUE |
prop |
If TRUE left.time and right.time are interpreted as proportions, if FALSE, they are interpreted as millisecond times |
This function extracts data from each segment of a trackdata object.
If 'prop=FALSE' the time arguments ('left.time' and 'right.time') are interpreted as millisecond times and each should be a vector with the same length as the number of segments in 'trackdata'. If 'prop=TRUE' the time arguments should be single values between zero (the onset of the segment) and one (the offset).
If 'right.time' is omitted then a single data point corresponding to 'left.time' for each segment is returned.
A trackdata object if both 'left.time' and 'right.time' are specified, otherwise a matrix if 'right.time' is unspecified and the trackdata object has multiple columns of data or a vector if right.time' is unspecified and the trackdata object has a single column of data.
Jonathan Harrington
# the data values of the trackdata object at the temporal midpoint
# (midvals is matrix of F1 and F2 data)
dip.fdat[1:10]
midvals <- dcut(dip.fdat, 0.5, prop=TRUE)
midvals[1:10,]
# the data values of the trackdata object between
# extending from 20
# (bet is a trackdata object of F1 and F2 values)
bet <- dcut(dip.fdat, 0.2, 0.8, prop=TRUE)
bet[1]
# the data values of the trackdata object at 30 ms after
# the start time of the trackdata object
# (time30 is a matrix of F1 and F2 data
times <- dip.fdat$ftime[,1]+30
times[1:10]
time30 <- dcut(dip.fdat, times)
time30[1:10]
# the data values of the trackdata object
# between the start time and 30 ms after the start time
# (int is a trackdata object of F1 and F2 values extending
# from the start of the diphthongs up to 30 ms after the diphthongs)
int <- dcut(dip.fdat, dip.fdat$ftime[,1], times)
int[1]Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.