Reputation: 309
I need to calculate the number of occurrences of specific events over specified time periods. Assume I have the following data:
set.seed(1453)
id = c(1,1,1,1,1,2,2,2,2,2)
x_1 = sample(0:1, 10, TRUE)
x_5 = sample(0:1, 10, TRUE)
date = c('2016-01-01',
'2016-02-01',
'2016-02-23',
'2016-03-04',
'2016-04-01',
'2016-01-01',
'2016-02-01',
'2016-02-23',
'2016-03-04',
'2016-04-01'
)
df = data.frame(id,date=as.Date(date),snapshot_date = as.Date(date)+1,x_1,x_5)
TABLE 1. (INPUT)
id date snapshot_date x_1 x_5
1 2016-01-01 2016-01-02 1 0
1 2016-02-01 2016-02-02 0 1
1 2016-02-23 2016-02-24 1 1
1 2016-03-04 2016-03-05 0 0
1 2016-04-01 2016-04-02 0 1
2 2016-01-01 2016-01-02 1 1
2 2016-02-01 2016-02-02 1 0
2 2016-02-23 2016-02-24 0 0
2 2016-03-04 2016-03-05 0 0
2 2016-04-01 2016-04-02 1 1
I need to calculate how many times x_1=1 and x_5=1 occurred within the last 3 months (per each month). So I first create dummy variables: if x_1 =1, then x_1_n = TRUE. Otherwise, x_1_n = FALSE. Similarly, for x_5_n. I also create the dates for three months going backwards.
df$x_1_n <- ifelse((df$x_1 ==1), TRUE, FALSE)
df$x_5_n <- ifelse(df$x_5==1, TRUE, FALSE)
library(lubridate)
for (i in 1:3) {
DATE_MO <- as.Date(df$snapshot_date) %m-% months(i)
df[,paste0("DATE_MO", i)] <- DATE_MO
}
I have variables x_1, x_5. I need to write a loop that goes through all of those variables x_1,x_5 and calculate the number of occurrences between certain dates. The original code runs and is correct. But I want to see how to simplify it using the for loop so that I don't have to manually copy-paste the code for each x_1 and x_5 as the number of x_'s and dates are bigger in the original version.
library(data.table)
df <- data.table(df)
df[,c("x1_dminus_mo1",
"x1_dminus_mo2",
"x1_dminus_mo3"
) :=. (df[x_1_n][df[,.(id,DATE_MO1,snapshot_date)], on=.
(id, date >= DATE_MO1, date < snapshot_date), .N, by = .EACHI] $N
,
df[x_1_n][df[,.(id,DATE_MO2, DATE_MO1)], on=.
(id, date >= DATE_MO2, date < DATE_MO1), .N, by = .EACHI] $N
,
df[x_1_n][df[,.(id,DATE_MO3, DATE_MO2)], on=.
(id, date >= DATE_MO3, date < DATE_MO2), .N, by = .EACHI] $N
)]
df[,c("x5_dminus_mo1",
"x5_dminus_mo2",
"x5_dminus_mo3"
) :=. (df[x_5_n][df[,.(id,DATE_MO1,snapshot_date)], on=.
(id, date >= DATE_MO1, date < snapshot_date), .N, by = .EACHI] $N
,
df[x_5_n][df[,.(id,DATE_MO2, DATE_MO1)], on=.
(id, date >= DATE_MO2, date < DATE_MO1), .N, by = .EACHI] $N
,
df[x_5_n][df[,.(id,DATE_MO3, DATE_MO2)], on=.
(id, date >= DATE_MO3, date < DATE_MO2), .N, by = .EACHI] $N
)]
I want to get the following table but using the loop.
TABLE 2 (OUTPUT)
df[,c(1,2,4,11,12,13)]
id date x_1 x1_dminus_mo1 x1_dminus_mo2 x1_dminus_mo3
1 2016-01-01 1 1 0 0
1 2016-02-01 0 0 1 0
1 2016-02-23 1 1 1 0
1 2016-03-04 0 1 0 1
1 2016-04-01 0 0 1 0
2 2016-01-01 1 1 0 0
2 2016-02-01 1 1 1 0
2 2016-02-23 0 1 1 0
2 2016-03-04 0 0 1 1
2 2016-04-01 1 1 0 1
Upvotes: 0
Views: 83
Reputation: 309
Thank to @Frank, I've found the right path. Here is the solution:
for (i in c(1,5)){
col = paste0("x_",i)
df[,paste0("new_dminus_mo1_x", i)] <- df[, .SD[.(1), on=col]][df[,.(id,DATE_MO1,snapshot_date)], on=.
(id, date >= DATE_MO1, date < snapshot_date), .N, by = .EACHI] $N
df[,paste0("new_dminus_mo2_x",i)] <- df[, .SD[.(1), on=col]][df[,.(id,DATE_MO2,DATE_MO1)], on=.
(id, date >= DATE_MO2, date < DATE_MO1), .N, by = .EACHI] $N
df[,paste0("new_dminus_mo3_x",i)] <- df[, .SD[.(1), on=col]][df[,.(id,DATE_MO3,DATE_MO2)], on=.
(id, date >= DATE_MO3, date < DATE_MO2), .N, by = .EACHI] $N
}
Upvotes: 3
Reputation: 66819
I would create a long-form table so that only one join needs to be done per column:
lookup = melt(DT[, lapply(0:3, function(x) snapshot_date %m-% months(x)), by=id],
id="id",
meas = list(2:4, 3:5),
value.name = c("d_up", "d_dn"))
lookup[, rn := rowid(variable), by=id]
cols = c("x_1", "x_5")
for (k in cols) lookup[, paste0("n_", k) :=
DT[.(1), on=k][.SD, on=.(id, date >= d_dn, date < d_up), .N, by=.EACHI]$N][]
id variable d_up d_dn rn n_x_1 n_x_5
1: 1 1 2016-01-02 2015-12-02 1 1 0
2: 1 1 2016-02-02 2016-01-02 2 0 1
3: 1 1 2016-02-24 2016-01-24 3 1 2
4: 1 1 2016-03-05 2016-02-05 4 1 1
5: 1 1 2016-04-02 2016-03-02 5 0 1
6: 2 1 2016-01-02 2015-12-02 1 1 1
7: 2 1 2016-02-02 2016-01-02 2 1 0
8: 2 1 2016-02-24 2016-01-24 3 1 0
9: 2 1 2016-03-05 2016-02-05 4 0 0
10: 2 1 2016-04-02 2016-03-02 5 1 1
11: 1 2 2015-12-02 2015-11-02 1 0 0
12: 1 2 2016-01-02 2015-12-02 2 1 0
13: 1 2 2016-01-24 2015-12-24 3 1 0
14: 1 2 2016-02-05 2016-01-05 4 0 1
15: 1 2 2016-03-02 2016-02-02 5 1 1
16: 2 2 2015-12-02 2015-11-02 1 0 0
17: 2 2 2016-01-02 2015-12-02 2 1 1
18: 2 2 2016-01-24 2015-12-24 3 1 1
19: 2 2 2016-02-05 2016-01-05 4 1 0
20: 2 2 2016-03-02 2016-02-02 5 0 0
21: 1 3 2015-11-02 2015-10-02 1 0 0
22: 1 3 2015-12-02 2015-11-02 2 0 0
23: 1 3 2015-12-24 2015-11-24 3 0 0
24: 1 3 2016-01-05 2015-12-05 4 1 0
25: 1 3 2016-02-02 2016-01-02 5 0 1
26: 2 3 2015-11-02 2015-10-02 1 0 0
27: 2 3 2015-12-02 2015-11-02 2 0 0
28: 2 3 2015-12-24 2015-11-24 3 0 0
29: 2 3 2016-01-05 2015-12-05 4 1 1
30: 2 3 2016-02-02 2016-01-02 5 1 0
id variable d_up d_dn rn n_x_1 n_x_5
meas = list(2:4, 3:5)
just "melts" columns 2:4 together into one column, and similarly for 3:5.
Long form also has the benefit that you don't need to spend too much time working on naming conventions for columns containing similar data ("DATE_MO[x]", "new_dminus_mo[x]_x", etc).
I prefer this format (with separate long-form tables), but an "update join" can recover columns from DT here (with repeating values):
DT[, rn := rowid(id)]
DTcols = setdiff(names(DT), names(lookup))
lookup[DT, on=.(id, rn), (DTcols) := mget(paste0("i.", DTcols))]
id variable d_up d_dn rn n_x_1 n_x_5 date snapshot_date x_1 x_5
1: 1 1 2016-01-02 2015-12-02 1 1 0 2016-01-01 2016-01-02 1 0
2: 1 1 2016-02-02 2016-01-02 2 0 1 2016-02-01 2016-02-02 0 1
3: 1 1 2016-02-24 2016-01-24 3 1 2 2016-02-23 2016-02-24 1 1
4: 1 1 2016-03-05 2016-02-05 4 1 1 2016-03-04 2016-03-05 0 0
5: 1 1 2016-04-02 2016-03-02 5 0 1 2016-04-01 2016-04-02 0 1
6: 2 1 2016-01-02 2015-12-02 1 1 1 2016-01-01 2016-01-02 1 1
7: 2 1 2016-02-02 2016-01-02 2 1 0 2016-02-01 2016-02-02 1 0
8: 2 1 2016-02-24 2016-01-24 3 1 0 2016-02-23 2016-02-24 0 0
9: 2 1 2016-03-05 2016-02-05 4 0 0 2016-03-04 2016-03-05 0 0
10: 2 1 2016-04-02 2016-03-02 5 1 1 2016-04-01 2016-04-02 1 1
11: 1 2 2015-12-02 2015-11-02 1 0 0 2016-01-01 2016-01-02 1 0
12: 1 2 2016-01-02 2015-12-02 2 1 0 2016-02-01 2016-02-02 0 1
13: 1 2 2016-01-24 2015-12-24 3 1 0 2016-02-23 2016-02-24 1 1
14: 1 2 2016-02-05 2016-01-05 4 0 1 2016-03-04 2016-03-05 0 0
15: 1 2 2016-03-02 2016-02-02 5 1 1 2016-04-01 2016-04-02 0 1
16: 2 2 2015-12-02 2015-11-02 1 0 0 2016-01-01 2016-01-02 1 1
17: 2 2 2016-01-02 2015-12-02 2 1 1 2016-02-01 2016-02-02 1 0
18: 2 2 2016-01-24 2015-12-24 3 1 1 2016-02-23 2016-02-24 0 0
19: 2 2 2016-02-05 2016-01-05 4 1 0 2016-03-04 2016-03-05 0 0
20: 2 2 2016-03-02 2016-02-02 5 0 0 2016-04-01 2016-04-02 1 1
21: 1 3 2015-11-02 2015-10-02 1 0 0 2016-01-01 2016-01-02 1 0
22: 1 3 2015-12-02 2015-11-02 2 0 0 2016-02-01 2016-02-02 0 1
23: 1 3 2015-12-24 2015-11-24 3 0 0 2016-02-23 2016-02-24 1 1
24: 1 3 2016-01-05 2015-12-05 4 1 0 2016-03-04 2016-03-05 0 0
25: 1 3 2016-02-02 2016-01-02 5 0 1 2016-04-01 2016-04-02 0 1
26: 2 3 2015-11-02 2015-10-02 1 0 0 2016-01-01 2016-01-02 1 1
27: 2 3 2015-12-02 2015-11-02 2 0 0 2016-02-01 2016-02-02 1 0
28: 2 3 2015-12-24 2015-11-24 3 0 0 2016-02-23 2016-02-24 0 0
29: 2 3 2016-01-05 2015-12-05 4 1 1 2016-03-04 2016-03-05 0 0
30: 2 3 2016-02-02 2016-01-02 5 1 0 2016-04-01 2016-04-02 1 1
id variable d_up d_dn rn n_x_1 n_x_5 date snapshot_date x_1 x_5
Or reshape it to wide format and update-join back to DT:
wDT = dcast(lookup, id + rn ~ variable, value.var = paste0("n_", cols))
id rn n_x_1_1 n_x_1_2 n_x_1_3 n_x_5_1 n_x_5_2 n_x_5_3
1: 1 1 1 0 0 0 0 0
2: 1 2 0 1 0 1 0 0
3: 1 3 1 1 0 2 0 0
4: 1 4 1 0 1 1 1 0
5: 1 5 0 1 0 1 1 1
6: 2 1 1 0 0 1 0 0
7: 2 2 1 1 0 0 1 0
8: 2 3 1 1 0 0 1 0
9: 2 4 0 1 1 0 0 1
10: 2 5 1 0 1 1 0 0
DT[, rn := rowid(id)]
wDTcols = setdiff(names(wDT), names(DT))
DT[wDT, on=.(id, rn), (wDTcols) := mget(paste0("i.", wDTcols))]
id date snapshot_date x_1 x_5 rn n_x_1_1 n_x_1_2 n_x_1_3 n_x_5_1 n_x_5_2 n_x_5_3
1: 1 2016-01-01 2016-01-02 1 0 1 1 0 0 0 0 0
2: 1 2016-02-01 2016-02-02 0 1 2 0 1 0 1 0 0
3: 1 2016-02-23 2016-02-24 1 1 3 1 1 0 2 0 0
4: 1 2016-03-04 2016-03-05 0 0 4 1 0 1 1 1 0
5: 1 2016-04-01 2016-04-02 0 1 5 0 1 0 1 1 1
6: 2 2016-01-01 2016-01-02 1 1 1 1 0 0 1 0 0
7: 2 2016-02-01 2016-02-02 1 0 2 1 1 0 0 1 0
8: 2 2016-02-23 2016-02-24 0 0 3 1 1 0 0 1 0
9: 2 2016-03-04 2016-03-05 0 0 4 0 1 1 0 0 1
10: 2 2016-04-01 2016-04-02 1 1 5 1 0 1 1 0 0
Upvotes: 3