Question

My original data frame is this:
x

Team  Date   variable  value
A 2012-07-01 Score      13
A 2012-07-02 Score      12
A 2012-07-03 Score      2097
A 2012-07-04 Score      45
A 2012-07-05 Score      41
A 2012-07-06 Score      763

need to to be like this

z
    Team 2012-07-01 2012-07-02 2012-07-03 2012-07-04 2012-07-05 2012-07-06 
    A     13         12          2097      45        41         763

library(reshape)
z<-cast(x, Team + variable ~ Date)

I get a warning message stating this:

Aggregation requires fun.aggregate: length used as default

Answer 1

Use dcast from reshape2 package and it’ll work!

x <- read.table(text='Team  Date   variable  value
A 2012-07-01 Score      13
A 2012-07-02 Score      12
A 2012-07-03 Score      2097
A 2012-07-04 Score      45
A 2012-07-05 Score      41
A 2012-07-06 Score      763', header=T)

library(reshape2)
dcast(x, Team + variable ~ Date)
 Team variable 2012-07-01 2012-07-02 2012-07-03 2012-07-04 2012-07-05 2012-07-06
1    A    Score         13         12       2097         45         41        763

Edit:

You can use reshape function from stats. No additional package is required as above.

Y <- reshape(x, v.names='value', idvar='Team', timevar='Date',direction='wide')
names(Y) <- sub('value.', '', names(Y))
Y
  Team variable 2012-07-01 2012-07-02 2012-07-03 2012-07-04 2012-07-05 2012-07-06
1    A    Score         13         12       2097         45         41        763