r - Reshaping dataset

Question

I am just wondering if you could guide me to the right direction about how can I reshape a dataset based on a specific criteria to arrange by hours, for example, I have the follwing example dataset:

I am trying to reshape the dataset to look like this:

how can I proceed with this reshaping please? Many Thanks.

My sample data:

data = structure(list(date = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L), .Label = "Jan-97", class = "factor"), day = c(1L, 
1L, 1L, 1L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L), hour = c(1L, 2L, 
3L, 4L, 1L, 2L, 3L, 4L, 1L, 2L, 3L, 4L), Value = c(65L, 29L, 
31L, 42L, 42L, 52L, 61L, 57L, 55L, 52L, 57L, 46L)), .Names = c("date", 
"day", "hour", "Value"), class = "data.frame", row.names = c(NA, 
-12L))

Answer 1

This uses the reshape2 package. I am sure it can be done with the reshape function, but I am not as facile with that.

library("reshape2")
dcast(data, date+day~hour, value.var="Value")

which gives

> dcast(data, date+day~hour, value.var="Value")
    date day  1  2  3  4
1 Jan-97   1 65 29 31 42
2 Jan-97   2 42 52 61 57
3 Jan-97   3 55 52 57 46

If you don't like the names from that, you can change them afterwards.

widedata <- dcast(data, date+day~hour, value.var="Value")
names(widedata)[-(1:2)] <- paste0("hour",names(widedata[-(1:2)]))

so widedata is:

> widedata
    date day hour1 hour2 hour3 hour4
1 Jan-97   1    65    29    31    42
2 Jan-97   2    42    52    61    57
3 Jan-97   3    55    52    57    46