[Question] Should the `include.timepoint.column` give normalized timepoints (i.e., starting at 1 for each track)?

[burgerga]

If I have the following data.frame

test.df <- data.frame(id = c(1,1,2), t = c(1,2,2) * 0.1, x = runif(3), y = runif(3), 
                      z = runif(3))
test.df

  id   t         x         y         z
1  1 0.1 0.2522754 0.3752993 0.5761627
2  1 0.2 0.4081247 0.2668070 0.7371169
3  2 0.2 0.4610473 0.6297668 0.8011669

then

as.data.frame(as.tracks(test.df), include.timepoint.column = T)

gives

  id timepoint   t         x         y         z
1  1         1 0.1 0.2522754 0.3752993 0.5761627
2  1         2 0.2 0.4081247 0.2668070 0.7371169
3  2         1 0.2 0.4610473 0.6297668 0.8011669

whereas I would expect

  id timepoint   t         x         y         z
1  1         1 0.1 0.2522754 0.3752993 0.5761627
2  1         2 0.2 0.4081247 0.2668070 0.7371169
3  2         2 0.2 0.4610473 0.6297668 0.8011669

Is the first the intended behavior?