for(t in 1921:2017) {
nam <- paste("", t, sep = "")
assign(nam, window(aCPI_gr, start=c(t,1), end=c(t,12)))
}
aCPI_gr_y <- cbind(`1921`: `2017`) #doesn't work
This loop is generating vectors with CPI data from every month per year. Now i would like to pack all of them in a data frame with cbind, but i am of course to lazy to type every year-vector by hand in the cbind function. is there an easy way to avoid typing every year-vector by hand? something like cbind(1921:2017)
1) matrix If you have a monthly unidimensional ts series spanning 97 years, such as the test series tser below, then this will convert it to a 12 x 97 matrix with one year per column. The dimnames argument can be omitted if you don't need the names.
tser <- ts(seq_len(12 * 97), start = 1921, freq = 12) # test data
m <- matrix(tser, 12, dimnames = list(month = 1:12, year = 1921:2017))
2) tapply An alternative is:
tapply(tser, list(month = cycle(tser), year = as.integer(time(tser))), c)
