Adding missing date values in a data frame with multiple observation periods

Question

Thanks in advance.

I am trying to add missing date values that were not included in a observation period for three different individuals.

My data look like t

Answer 1

Hers's a dplyr solution. The result, based on the sample data, is a data.frame with 89 rows, I hope that's what you intended to get.

require(dplyr)

PostData %>%
  mutate(Date = as.Date(as.character(Date))) %>%
  group_by(IndID) %>%
  do(left_join(data.frame(IndID = .$IndID[1], Date = seq(min(.$Date), max(.$Date), 1)), ., 
                       by=c("IndID", "Date"))) %>%
  mutate(Event = ifelse(is.na(Event), 0, Event))

#   IndID       Date Event Number Percent
#1    P01 2011-03-04     1      2   0.390
#2    P01 2011-03-05     0     NA      NA
#3    P01 2011-03-06     0     NA      NA
#4    P01 2011-03-07     0     NA      NA
#5    P01 2011-03-08     0     NA      NA
#6    P01 2011-03-09     0     NA      NA 
#7    P01 2011-03-10     0     NA      NA
#8    P01 2011-03-11     1      2   0.975
#...
#84   P06 2012-01-25     0     NA      NA
#85   P06 2012-01-26     0     NA      NA
#86   P06 2012-01-27     1      4   0.758
#87   P06 2012-01-28     0     NA      NA
#88   P06 2012-01-29     0      8   0.290
#89   P06 2012-01-30     0      1   0.150