[R] adding labels to tapply results

[Dieter Menne]

eric lee <ericlee100 <at> gmail.com> writes:

> How do I get labels onto the output from tapply?  I need the labels to merge
> the output with another data frame.  Thanks.
> 
> eric
> 
> d <- data.frame(cbind(x=1:3, y=1:10))
> a <- with(d, tapply(y, x, sum))
> 

By taking the warning seriously. 

> d <- data.frame(cbind(x=1:3, y=1:10))
Warning message:
In cbind(x = 1:3, y = 1:10) :
  number of rows of result is not a multiple of vector length (arg 1)

 d <- data.frame(cbind(x=101:110, y=1:10))
 a <- with(d, tapply(y, x, sum))
 a

#101 102 103 104 105 106 107 108 109 110 
#  1   2   3   4   5   6   7   8   9  10 
 
Dieter