Convert a list of variables to list of tracklets.
Source:R/convert2Tracklets.R
convert2Tracklets.RdGiven a list containing vectors corresponding to the various variable of tracking data the function returns a list of data frames corresponding to the data for each tracklet based on tracklets identity.
Arguments
- trackDatList
A list of vector corresponding to the variable characterizing the tracking data.
- by
A character vector identifying the tracklets to join by (default = 'identity').
Examples
set.seed(2023)
# generate some dummy tracklets
## start to specify some parameters to generate tracklets
TrackN <- 3 # the number of tracklet to simulate
TrackL <-
1:1000 # the length of the tracklets or a sequence to randomly sample tracklet length
id <- 0
TrackList <- MoveR::trackletsClass(stats::setNames(lapply(lapply(seq(TrackN), function(i)
trajr::TrajGenerate(sample(TrackL, 1), random = TRUE, fps = 1)), function(j) {
id <<- id + 1
data.frame(
x.pos = j$x - min(j$x),
y.pos = j$y - min(j$y),
frame = j$time,
identity = paste("Tracklet", id, sep = "_")
)
}), seq(TrackN)))
# convert the list of tracklets to a simple list of variables
trackDatList <- MoveR::convert2List(TrackList)
str(trackDatList)
#> List of 5
#> $ x.pos : num [1:1738] 15.3 17.5 19.5 20.6 21.9 ...
#> $ y.pos : num [1:1738] 7.13 6.64 5.92 4.52 3.17 ...
#> $ frame : num [1:1738] 0 1 2 3 4 5 6 7 8 9 ...
#> $ identity : chr [1:1738] "Tracklet_1" "Tracklet_1" "Tracklet_1" "Tracklet_1" ...
#> $ trackletId: chr [1:1738] "1" "1" "1" "1" ...
#> - attr(*, "class")= chr "varList"
# convert back the list of variables to a list of tracklet based on tracklets identity
trackDat <- MoveR::convert2Tracklets(trackDatList, by = "trackletId")
str(trackDat) # display only the three first elements (dataframes) of the list
#> List of 3
#> $ 1:'data.frame': 886 obs. of 5 variables:
#> ..$ x.pos : num [1:886] 15.3 17.5 19.5 20.6 21.9 ...
#> ..$ y.pos : num [1:886] 7.13 6.64 5.92 4.52 3.17 ...
#> ..$ frame : num [1:886] 0 1 2 3 4 5 6 7 8 9 ...
#> ..$ identity : chr [1:886] "Tracklet_1" "Tracklet_1" "Tracklet_1" "Tracklet_1" ...
#> ..$ trackletId: chr [1:886] "1" "1" "1" "1" ...
#> $ 2:'data.frame': 280 obs. of 5 variables:
#> ..$ x.pos : num [1:280] 129 131 133 135 136 ...
#> ..$ y.pos : num [1:280] 106 106 107 108 109 ...
#> ..$ frame : num [1:280] 0 1 2 3 4 5 6 7 8 9 ...
#> ..$ identity : chr [1:280] "Tracklet_2" "Tracklet_2" "Tracklet_2" "Tracklet_2" ...
#> ..$ trackletId: chr [1:280] "2" "2" "2" "2" ...
#> $ 3:'data.frame': 572 obs. of 5 variables:
#> ..$ x.pos : num [1:572] 88.5 90.1 92 93.8 95.1 ...
#> ..$ y.pos : num [1:572] 35.5 34.5 33.7 32.8 31.7 ...
#> ..$ frame : num [1:572] 0 1 2 3 4 5 6 7 8 9 ...
#> ..$ identity : chr [1:572] "Tracklet_3" "Tracklet_3" "Tracklet_3" "Tracklet_3" ...
#> ..$ trackletId: chr [1:572] "3" "3" "3" "3" ...
#> - attr(*, "class")= chr "tracklets"