hts in R: Convert data.frame into a gts object I'm  a month-old user of RStudio.
Currently, I'm working with hierarchical time series analysis with the hts package. After reading my .csv data below, 
      WEEKNUM     SITE   OPERATIONS    ATTRITION
 1    201502      DAVAO   PRODUCTION         0
 2    201503      DAVAO   PRODUCTION         3
 3    201504      DAVAO   PRODUCTION         8
 4    201505      DAVAO   PRODUCTION         6
 5    201506      DAVAO   PRODUCTION         9
 6    201507      DAVAO   PRODUCTION         4
 7    201508      DAVAO   PRODUCTION         9
 ...
 592  201623      WM      TRAINING           0

I've tried creating the matrix out of it with these codes:

Then a matrix was successfully created, however the values were rnorm generated:
 
How do I replace them with the original grouped series values?
Or how do I start hts better, with my data import? 
Thanks and more power! :)
 A: It's not a statistics but a program topic....Supposition in this example: There are four SITE and two OPERATION.
(if not, you'll modify each number in below code.)
# example data as .csv data (you needn't)
df <- data.frame(WEEKNUM=rep(c(201502:201552, 201601:201623), 8),
                 SITE = rep(LETTERS[1:4], each=74),
                 OPERATIONS = rep(LETTERS[11:12], each=296),
                 ATTRITION = rnorm(592))

# If undone, you'll sort the data (1st key is SITE, 2nd is OPERATIONS, last is WEEKNUM).
df <- df[order(df$SITE, df$OPERATIONS, df$WEEKNUM),]
df$test <- paste(df$SITE, df$OPERATIONS, seq=" ") # make the row to check

matrix(df$test, nrow=74)        # checking. If you succeed, each column consist of one factor.
abc <- ts(matrix(df$ATTRITION, nrow=74), start=c(2015,2), frequency=52)   # creating time-series objects
SITE <- rep(levels( df$SITE ), each=2)        # each=2; the number of OPERATIONS
OPERATIONS <- rep(levels( df$OPERATIONS ), 4) # 4; the number of SITE
gc <- rbind(SITE, OPERATIONS)                 # a matrix consists of strings
rownames(gc) <- c("SITE", "OPERATIONS")
x <- gts(abc, groups = gc)                    # finish

