data/scripts/fill_NAs.R

   1 fill_NAs = function(file)
   2 {
   3     dat_with_date = read.csv(file)
   4     dat = dat_with_date[,-1] #get rid of date column
   5
   6     line = 1
   7     n = nrow(dat)
   8     p = ncol(dat)
   9     last_noNA_indices = rep(0, p)
  10     while (line <= n)
  11     {
  12         for (i in 1:p)
  13         {
  14             if (!is.na(dat[line,i]))
  15             {
  16                 if (last_noNA_indices[i] < line-1)
  17                 {
  18                     #do some completion
  19                     meanVal = ifelse( last_noNA_indices[i]>0,
  20                         0.5*(dat[last_noNA_indices[i],i]+dat[line,i]),
  21                         dat[line,i] )
  22                     dat[(last_noNA_indices[i]+1):(line-1),i] = meanVal
  23                 }
  24                 last_noNA_indices[i] = line
  25             }
  26         }
  27         line = line + 1
  28     }
  29
  30     #complete until end if needed
  31     for (i in 1:p)
  32     {
  33         if (last_noNA_indices[i] < n)
  34             dat[(last_noNA_indices[i]+1):n,i] = dat[last_noNA_indices[i],i]
  35     }
  36
  37     dat_with_date[,2:(p+1)] = dat
  38     write.csv(dat_with_date, "NONA.csv", row.names=FALSE)
  39 }