Re: [R] Error in tapply when reordering levels of a factor

On Feb 27, 2010, at 10:01 PM, Thomas Levine wrote: I have this grades$grade ... [4009] A B A- A- A- B+ A A- B+ B A B B B A A- A A- A- B+ A- A A B+ [4033] A- A- A- A A- B A A A- A Levels: A A- A+ B B- B+ C C+ I want to change the order of the levels reorder(grades$grade

[R] Error in tapply when reordering levels of a factor

I have this > grades$grade ... [4009] A B A- A- A- B+ A A- B+ B A B B B A A- A A- A- B+ A- A A B+ [4033] A- A- A- A A- B A A A- A Levels: A A- A+ B B- B+ C C+ I want to change the order of the levels > reorder(grades$grade,c('A+','A','A-','B+','B','B-','C+','C')) Error in tapply