I have a daily dataset as following and trying to convert it to weekly. I could do it to weekly but I could not make it for each group.
group_id date value
group_1 2013-12-1 3
group_1 2013-12-2 4
group_1 2013-12-3 2
.
.
.
group_2 2014-1-1 5
group_2 2014-1-2 8
group_2 2014-1-3 6
.
.
I would like to convert it to:
group_id week1/date week2/date week3/date week4/date ......
group_1 3 5 6 4
group_2 9 7 10 13
group_3 . . . .
group_4 . . . .
.
.