Usage
"as.tracks"(x, id.column = 1, time.column = 2, pos.columns = c(3, 4, 5), scale.t = 1, scale.pos = 1, ...)
Arguments
x
the data frame to be coerced to a tracks object.
id.column
index or name of the column that contains the track ID.
time.column
index or name of the column that contains elapsed time.
pos.columns
vector containing indices or names of the columns that contain
the spatial coordinates. If this vector has two entries and the second entry is NA,
e.g. c('x',NA) or c(5,NA) then all columns from the indicated column
to the last column are used. This is useful when reading files where the exact number
of spatial dimensions is not known beforehand.
scale.t
a value by which to multiply each time point. Useful for changing units,
or for specifying the time between positions if this is not contained in the file
itself.
scale.pos
a value, or a vector of values, by which to multiply each spatial
position. Useful for changing units.
...
further arguments to be passed to read.csv, for instance
sep="\t" can be useful for tab-separated files.