My sample data looks like this:
data <- read.table(header=T, text='
pid measurement1 Tdays1 measurement2 Tdays2 measurement3 Tdays3 measurment4 Tdays4
1 1356 1435 1483 1405 1563 1374 NA NA
2 943 1848 1173 1818 1300 1785 NA NA
3 1590 185 NA NA NA NA 1585 294
4 130 72 443 70 NA NA 136 79
4 140 82 NA NA NA NA 756 89
4 220 126 266 124 NA NA 703 128
4 166 159 213 156 476 145 776 166
4 380 189 583 173 NA NA 586 203
4 353 231 510 222 656 217 526 240
4 180 268 NA NA NA NA NA NA
4 NA NA NA NA NA NA 580 278
4 571 334 596 303 816 289 483 371
')
Now i would like it to look something like this:
PID Time (days) Value
1 1435 1356
1 1405 1483
1 1374 1563
2 1848 943
2 1818 1173
2 1785 1300
3 185 1590
... ... ...
How would i tend to get there? I have looked up some things about wide to longformat, but it doesn't seem to do the trick. Kind regards, and thank you in advance.
Here is a base R option
u <- cbind(
data[1],
do.call(
rbind,
lapply(
split.default(data[-1], ceiling(seq_along(data[-1]) / 2)),
setNames,
c("Value", "Time")
)
)
)
out <- `row.names<-`(
subset(
x <- u[order(u$pid), ],
complete.cases(x)
), NULL
)
such that
> out
pid Value Time
1 1 1356 1435
2 1 1483 1405
3 1 1563 1374
4 2 943 1848
5 2 1173 1818
6 2 1300 1785
7 3 1590 185
8 3 1585 294
9 4 130 72
10 4 140 82
11 4 220 126
12 4 166 159
13 4 380 189
14 4 353 231
15 4 180 268
16 4 571 334
17 4 443 70
18 4 266 124
19 4 213 156
20 4 583 173
21 4 510 222
22 4 596 303
23 4 476 145
24 4 656 217
25 4 816 289
26 4 136 79
27 4 756 89
28 4 703 128
29 4 776 166
30 4 586 203
31 4 526 240
32 4 580 278
33 4 483 371